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Full text of "The Electrical experimenter"

Beginning^lMy Inventions," by Nikola Tesla 






a 



FEB. 
19 19 
20 CTS, 



OVER 



ILLUST. 



Electrical 
Experimenter 

SCIENCE AND INVENTION 



THE TESLA 

WIRELESS LIGHT 

SEEPAGE 6 92 



r • v* 








CIRCULATION OF 



.WV ^h. w^ 



W ^LkAA 



MEN WANTED AS 



CERTIFICATED 
ELECTRICIANS 



This is the Electrical Age, and this wonderful new profession is calling you. The 
demand for expert Electricians is greater every year and the salaries higher. Elec- 
tricity is truly the greatest motive power in the world, to-day, and now is the time to 
enter this profession. 



YOU CAN DO THIS 






AFTER HOME STUDY 

$3620 TO SIOOM A WEEK 



You can earn $36 to $100 a week and more as an Expert Electrician. If you have a 
common school education I can train you in a few months at home. Big lighting and 
power companies, municipalities, and manufacturers are always seeking trained men to 
handle their Electrical prohlems. 
SPECI.^L OFFER: Owing to the bic (Icmaiul for trained Electricians in tlie Government Service I am making 
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I Guarantee Satisfaction 

Every stiidtnl receives our Sealed Guarantee Bond, which f;uarantccs to return every penny of his money if he 
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hundreds of my students, and I know what I can do for any ambitious young man who will give me a little of his 
spare time each day. 

FREE ELECTRICAL OUTFIT 



MAIL THIS COU 



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CHIEF ENGINEER. *,. "1. ^ooke. Chicago Engineering Works. 
Hepi 22, jjj Ciss St..' CJhicago, Illinois. 

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For the next 30 days I am giving each student an Outfit of Electrical 

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My instruction is by practical methods and this outfit is used in xvorking 

'^ut the lessons. Practical training with the theory makes perfect. I am Chief 

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I This is the only Correspondence School in America that has fully equipped 

' Electrical Shops where students may come for special instruction. 

I If you are in real earnest I want to send you my Book — "How to 

Become an Electrical Expert." It's free. No matter how many other schools 
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practical — Write today. 

j CHIEF ENGINEER L. L. COOKE 

I CHICAGO ENGINEERING WORKS 



Deot. 22 



441 CASS STREET, CHICAGO. ILL. 



February, 1919 



ELECTRICAL EXPERIMENTER 



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You Can Now Know 

ELECTRICITY 

As Experts Know It 

When we observe the ever-increasing applications and usages 
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electrical work. 

Actual working facts 

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^^. . ^ GUY H. PEIFER. 

Chief, Doplan Silk Corporation. Hazleton. Pa 



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lectrical Experimesiter 

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Publisht by Experimenter Publishing Companj, Inc. (H. Gemsbtck. Preiident; S. Gemsback. Tre««urer;) 233 Fulton Street, New York 



Vol. VI Whole No. 70 



FEBRUARY. 1919 



No. 10 



NIKOLA TESLA AND HIS WIRELESS LIGHT Front Cover 

From a painting by George W all. 

TIDAL POWER PROBLEM SOLVED .\T LAST 685 

PRODUCING RAIN BY ELECTRICITY AND X-RAYS 687 

MOVING PLATFORM FOR NEW YORK'S CROSSTOWN SUB- 

WAY By H. Winfield Secor 688 

THE UNKNOWN PURPLE By Dorothy Kant 690 

ZEPPELIN FLIES FROM BULGARIA TO KHARTOUM AND RE- 
TURN WITHOUT STOPPING 691 

FAMOUS SCIENTIFIC ILLUSIONS By Dr. Nikola Tesla 692 

SOLDIERS' ILLS CURED BY ELECTRICITY 695 

MY INVENTIONS— NO. 1 OF A SERIES 

Bv Dr. Nikola Tesla. Exclusive Feature. 696 
•SUBWAYS OF DOWNTOWN NEW YORK . 

From a painting by George Wall. 699 
'POPULAR ASTRONOMY— THE MILKY WAY 

By Isabel M. Lewis, of the U. S. Naval Observatory 700 

■WOMEN NOW TRAINED AS METER READERS 702 

LARGEST ELECTRIC CRANE LIFTS COMPLETE TUG BOAT... 703 
SELLING ELECTRICITY BY THE "CAN 704 



LATEST ELECTRICAL APPARATUS AND NOVELTIES 705 

WIRELESS LEGISLATION NEWS 706 

RADIO DEPARTMENT— PRESIDENT WILSON IN TOUCH WITH 

AMERICA ON LAND OR SEA— VIA RADIO 708 

VACUUM VALVE ACTION AND THE ELECTRIC CURRENT 

Bt K. G. Ormiston, Instructor in Radio 710 
THE VORTEX RING THEORY OF THE ELECTRON 

By F. W. Russell and J. L. Clifford 712 
"BALL LIGHTNING" EXPERIMENTS. .By Samuel S. Weisiger, Jr. 714 
A USEFUL ELECTRICAL LABORATORY SWITCHBOARD 

By H. Danner 715 
EXPERIMENTS IN RADIO-ACTIVITY 

By Ivan Crawford. Part II. — ^Ionization 716 
EXPERIMENTAL MECHANICS— LESSON X..By Samuel D. Cohen 717 
EXPERIMENTAL CHEMISTRY— THIRTY-THIRD LESSON 

By Albert W. Wilsdon 718 

HOW-TO-MAKE-IT DEPARTMENT— PRIZE CONTEST 719 

WRINKLES, RECIPES AND FORMULAS. . .Edited by S. Gernsback 720 

LATEST PATENTS DIGEST 721 

WITH THE AMATEURS— LABORATORY PHOTO CONTEST 722 

PHONEY PATENT CONTEST 723 





Tlh® Mew Wk(gS®§§ 



»lj T will come as a profound shock to all 
5.^" wireless enthusiasts, scientific and amateur 




alike, that their present-day notions on 
wireless are totally erroneous and not based 
upon actual facts. For years we clung to 
the theory that a wireless message radiates 
from the aerial wires of the sending station 
and speeds over the surface of the earth thru the ether 
towards the receiving station. We thought that we were 
sending out pure Hertzian waves from our transmitters. 
We thought that we received these waves over the aerial 
wires of our receiving station. All of these theories are 
wrong and will be relegated shortly into the past along 
with the early notion that the earth stood still, while sun, 
moon and stars revolved around it. 

Remain only the physical facts that we did send and 
did receive messages without wires — but they are not 
sent by means of pure Hertz waves, nor do they go by 
way of the ether as radiations. 

In a highly illuminating article printed elsewhere in this 
issue, Nikola Tesla e.xplodes all of our present orthodox 
views as to wireless propagation and makes it clear that 
the earth is the sole medium thru which our wireless 
impulses travel, in the form of true conduction. Particu- 
larlv does this hold true for long distance messages: 
Here we are sending out a compound impulse three quar- 
ters of which is a galvanic current, traveling thru the con- 
diicting earth, the other quarter or less is in the form of 
Hertz waves, going by way of the ether. This explains 
why we can send signals to airplanes and vice versa ; but 
even here we probably have to do not with pure Hertz 
waves • it is almost certain that we have capacity-induc- 
tive effects as well. 

Tesla maintaining that there can be no long distance 
effects by radiations transmitted thru the ether, but 
rather only by currents thru the earth, it follows that in 
his opinion all our radio apparatus is designed and 
operated faultily. Indeed, this is not a brand new idea of 
the famous inventor. He has been preaching it ever 
since he took out his first patents and described his sys- 
tem in 1893— long before Marconi thought of wireless 



But he was preaching to a stone deaf scientific world. 

But how simple it all becomes when we stop to apply a 
little reason and logic to Tesla's claims. For instance, 
we can send radio impulses three to five times as far 
over salt water as over land. Why? Simply because 
the impulses go thru the water, which is a much better 
conductor than earth alone. If we were sending pure 
Hertzian waves, why do we connect one wire at both 
sending and receiving station to the ground? Hertz 
never dreamt of such a thing. If you are still uncon- 
vinced that the earth is the chief medium of transmission, 
disconnect your ground wires entirely and tr\' to send 
and receive. Now you may work with Hertz waves, but 
the distances you can bridge will be pitifully small. 

Already Tesla's logic is filtering into our radio scientists' 
minds. All the big stations are beginning to scrap their 
towers and aerial wires, at least for receiving. They 
now bury their "aerial" wires in the ground, and lo ! they 
can receive signals twice as far as before. Incredible, 
l)ut it is being done every day. And — -wonders upon 
wonders — how we will laugh at our present and past 
blindness — the static interference is fractically gone the 
minute we pull our aerial wires down and bury them ! 
Static Electricity? There never was a reason for having 
the bugaboo, for there is no "static" in the ground. 

But Tesla goes much farther. In time he will show the 
world wireless power transmission effected not by ether 
waves but by currents thru the earth, which is a first rate 
conductor. Like all big things, the problem is simple. 
At some point on the globe he will erect a station power- 
ful enough to charge the whole earth with electricity — 
and keep it charged. To do this we need about 10,000 
kilowatts. Then at any point on the globe the current 
can be tapt by means of suitable apparatus. Like a bell 
ringing transformer, connected to your supply line, no 
current is consumed unless you close the secondary cir- 
cuit. Tesla's world wireless works just that way. No 
current is consumed till it is tapt at the distant receiving 
station. 

H. Gernsback. 




The ELECTRICAL EXPERIMENTER U pubUsht on the 15lh ot each month at 233 
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A sample copy will be sent irratls on request. Checks and money orders should he drawn 
lo order of EXPERIilENTER Pt3LISHING CO,. INC. If you change your address 
Dotlfy us promptly, in order that copies are not miscarried or lost, A flreen wrapper In- 
dicates explratfoii. No ceplM tent attar explrmtlon. 

All communications and contributions to this Journal should be addrest to: Editor, 
EMICTBICAL EXPEHIMENTEE. 233 Fulton Street. New York. Unaccepted contribu- 



tions cannot be returned unless full postage has been Included. ALL accepted contribu- 
tions are paid for on publication, A special rate is paid for novel experiments: Bood 
photographs accompanying the m ar e highly desirable, 

ET-ECTBICAL EXPKRl.MENTER, Monthly, Entered as second-class matter at the 
New York Post OfUrP mider Act of Congress of March 3. 1879. Title registered U. S, 
Patent Offloe, Copyright. 1919. by E. P, Co,, Inc. New York, The Contents of this 
maaailne are copyrighted and must not be reproduced without giving full credit to the 
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682 



February, 1919 



ELECTRICAL EXPERIMENTER 



683 




Ei Paso, Teias, Oct. i, 1917. 
MR. CHARLES F. HAANEL. St. Uuis. Mo. 
In Rt "Tht Master Kty" 

My Dear Mr. Haanel: The value of an idea is 
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CHAS. A. HEARD. 



May 15, 1918. 

Dear Mr. Haanel : Ever since I have been old 
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THE LOWE OBSERVATORY 

Edgar Lucien Larkin, Director 

Los Angeles, Cal., Dec. 6, 1916. 
MR. CHAS. F. HAANEL, St. Louis, Mo. 

Dear Sir: _ Your booklet. Master Key, ought to 
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Detroit, Mich, May 28, 1917. 
Dear Sir: The words, "Your world will change 
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W. M. HOWE. 



which can throw 
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684 



ELECTRICAL EXPERIMENTER 



February, 1919 




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Vol. VI. Whole No. 70 



FEBRUARY, 1919 



Number 10 



Tidal Power Problem Solved at Last 



TIDAL power is one of those long 
dreamed of possibilities in engineer- 
ing which has occupied the minds 
of great philosophers for genera- 
tions. Why not, — for who can stand 
down by the ocean shore, or even by any 
large river having an appreciable tidal rise 
and fall, and fail to be imprest with the gi- 
gantic natural power here spread out be- 
fore us, and let go to waste for all these 
years. Think of it — tens of thousands, yes. 



That is the idea several engineers have 
had, but an English engineer Beems to 
have solved the problem successfully with 
his specially designed tidal turbines and 
triple basins. His name is J. O. Boving, 
and his scheme is so practical that it has 
been proposed for the development of elec- 
tric power from the tide water at the mouth 
of the River Dee. Mr. Boving's descrip- 
tion of the tidal power plant is as follows : 

.A.ltho the ( English ) Government a few 



ally speaking, the differences on the east 
coast are small, but on the west coast there 
are many river estuaries and other inlets 
which offer abundant possibilities for ob- 
taining power from the tides. 

Some years ago I had an opportunity of 
examining the possibilities of developing a 
tidal water power on the estuary of the 
River Dee, where the tidal differences are 
roughly thirty-fiz'e feet at highest Spring 
tide and thirteen feet at loi^esl neap tide. 




CopyriRht. !£!19, by B. P. Co. 



The Proposed River Dee Tidal Power Development As Designed By a Famous English Engineer — J. O. Boving. This View Shows His 
Two Basin Proposal Where the Area of the Impounded Water Would Amount To Forty-Four Square Miles. The Maximum Tidal Differ- 
ence Is In This Case About Thirty-Five Feet. A Large Railway Embankment Is a Part of the Scheme, This Railway to Connect Up 

the Welsh Railway System With Birkenhead and Liverpool. 



millions, of horse-power dissipating itself 
on our coastal and river shores every day in 
the year. To realize this fact fully we need 
but reflect for a moment. If the tide brings 
us a rise of several acres (many thousand 
cubic feet) of water, why let it fall again, 
uselessly? Allow the water to flow, without 
friction, into huge basins at high tide; trap 
it, and when the tide falls, permit the im- 
prisoned water to escape, but thru turbines. 
back to the tidal level. 



months ago took a very wise and necessary 
step in appointing a committee to inquire 
into the possiljilities of water power devel- 
opment in the British Isles, there is one 
aspect of the question which does not seem 
to have attracted adequate attention, and 
that is the utilization of tidal forcer. The 
rise and fall of the tides around the English 
coasts vary greatly, from a ma.ximuni of 
nearly fifty feet in some places on the west 
coast to only a few feet at others. Gener- 



The scheme put forward was to form a 
railway embankment across the mouth of 
the estuary so as to connect up the Welsh 
railway system with Birkenhead and Liver- 
pool. The area of the impounded water 
behind this dam was to be forty-four square 
miles. On account of local conditions it 
was not difficult to divide this basin into 
two equal parts, and to arrange these two 
inner basins, the sea forming the third, in 



685 



686 



ELECTRICAL EXPERIMENTER 



February, 1919 



such a way that a power station could be 
worked coiitinuotuJy under constant head 
and with constant output. The plan was 
roughly as follows : 

Supposing that we start with high tide, 
the flap gates leading from the sea to the 
high basin would be open, and the water 
would flow in and pass thru turbines into 
the lower basin, the automatic flap gates 
to this basin being closed by the water pres- 
sure outside. This flow would continue 
until the level in the sea equaled that in 
the high basin, when the flap valves to this 
would slowly close, [n the meantime the 



trie transmission easy. In such cases the 
surplus power might be used during the 
periods when it is available for pumping 
up water to such reservoirs, while during 
the intervals, when power is required, it 
could be obtained thru high-pressure tur- 
bines driven by the stored-up water supplied. 
It will perhaps he argued that this is a 
very elaborate and costly arrangement 
which would not pay. The problem in fact 
resolves itself to this: .Assuming (1) that 
an ordinarj- water power in a river was 
developed and used for commercial pur- 
poses during twelve hour= out of the 




RESERVO/R EMPTYING 

THRU TURBINES PIPES TO 
TURBINES 



^MW^ 




NOTE DIFFERENCE 
y INLEVELS 



ONE RESERVOIR ONLY 




a"-" STAGE" 
TURBINES STARTED-HEflD NOW /IVfllLflBLE 



POWER PL/tNT 




HIGH TIDE 
HIGH BASIN NO.I LEVEL 

y> 






FL/lP_0/fTES^ 



TURBINES TURNING 



T ■ ^^' ■" ■ LOW TIDE- 



2 BflSIN TIDAL POWER PLANT 
'RIVER DEE"OEVELOPMENT 




CLOSED BY 
PRESS URS 

OF WPTER 
/rr HIGH TIDE 



a*- 



CoBTTlght. 1919. by B. P. Co. 

Progressive Illustration Showing How the Tidal Power Plant Works. First Figure Shows 
How the Rising Tide Fills the Large Basin Or Reservoir With Water. At Full Tide the Sea 
Gates Are Closed and After the Tide Has Fallen a Few Feet, a Working "Head" Becomes 
Available As Fig. 2 Shows. The Impounded Water Discharges Thru Turbines Back to the 
Sea. Fig. 3 Shows a "Two Basin" Plant Which Discharges the Impounded Water In Two 
Stages, Giving Steadier Power Development. 

level in the high basin would slowly SINK 
as water was consumed, and the level in 
the low basin would INCREASE until the 
moment when the water level in the sea 
had fallen to such a point that the gates of 
the lower basin would open and discharge 
the water in it completely. On the rising 
tide a similar sequence would be followed, 
and a continuous development of power 
would thus be maintained. 

There are a great number of cases along 
the coast where it would be easy to create 
a reservoir at a considerable height adja- 
cent to the tidal power station, or at least 
within a distance which would maW<» elec- 



twenty-four and that it was a good com- 
mercial scheme under these conditions ; and 
(2) that a high pressure power develop- 
ment could be obtained by using stored 
water for twelve hours of the twenty-four, 
and that this also was a commercially good 
undertaking in itself; then it must be 
equally sound commercially to link the two 
together and produce power around the 
twenty-four hours. In the tidal scheme 
the only things added to the arrangement 
described above are pumps, which are a 
negligible factor in the general costs (they 
would correspond to something like $3.75 
per h. p.). The pipes thru which the water is 



pumped up are, of course, the same as those 
which return the water from the high pres- 
sure plant. Everj'thing else is in common. 

The calculation for such a scheme is sim- 
ple, and in the case referred to, assuming 
that in any case a bank was needed across 
the Dee mouth, for railway purposes, there 
is no doubt that this power development 
would pay well. In cases where two tidal 
plants of similar size are close together the 
necessary conditions could be realized by 
connecting them. There would be nothing 
novel in such plans ; the turbines would be 
of standard design, the variation in the 
head would be only such as would be al- 
lowable for in ordinary turbine plants, and 
there would be no need to bridge over any 
periods when the power developed fell 
much below the average power. 

However, in most cases it would be im- 
possible to develop the three-basin idea, and 
it would be necessary to rely only on one 
inner reservoir and the sea. Obviously un- 
der such conditions the engineer has to con- 
tend with very great variations in head and 
power. The great differences that occur 
in the tidal ranges at various times compel 
him to calculate his turbines for the average 
head derived from neap tides. 

The genera! idea of a one-reservoir tidal 
scheme is as follows : At the beginning of 
high tide the sluices are open fully and the 
water rushes into the inner reservoir, filling 
it up as quickly as possible. Then the gates 
are shut for a certain time, until the water 
level outside has fallen to give a desired 
difference in level between the reservoir and 
the sea. (See detailed illustration of one 
reservoir scheme herewith.) The turbines 
are now started and kept in operation under 
virtually constant head, while the level in 
the reservoir falls at the same time as the 
tide. Some time before the lowest level of 
the tide the turbines are shut off, the gates 
opened, and the remaining water in the res- 
ervoir allowed to rush out with the lowest 
tide. Then the gates are closed, the tide 
rises outside until the difference in level 
between the sea and the reservoir has again 
reached the agreed amount, the turbines are 
started, and the same procedure is gone 
thru for the rising tide as just described 
for the falling. Thus for certain definite 
periods power is obtained at a nearly con- 
stant rate, but in the intervals no power is 
produced. 

Up until now we have been satisfied to 
mine and burn coal, prospect for oil gush- 
ers, and, in fact, have tried out about every 
expensive source of power we could think 
of. This comes of prosperity. America is 
rich, and the keynote of the hour is "speed." 
Design, develop, build, — do all these things 
— say our great philosophers and educat- 
ors, but do them FAST. Speed is a fine 
thing — in its place ; but there is bound to 
be a big bill to pay, some day. Why not 
live and work efficiently; not necessarily in 
a slow, plodding, unenlightened way, but in 
an economical manner. Coal and oil will 
not last forever. If you have ever visited 
Holland, you have undoubtedly been im- 
prest with the simplicity of things, and 
those windmills. There is a fine bit of an- 
tique engineering. The Hollander is using 
an untaxable, free, and powerful source of 
natural power — the wind. Besides these 
you will find in all parts of Europe the 
ever-present water wheel and turbine. Ex- 
cellent, steady power, untaxed in most 
cases; but do the American farmers and 
developers put the free wind and water 
power to work ? Yes, they do NOT. They 
would rather spend a thousand dollars or 
so for a gasoline engine and then work 
their heads off for the rest of their lives 
buying gasoline and oil to run it with. You 
can see hundreds of windmills and vrater- 
wheels rusting to pieces all over the coun- 
try. A great pity and a prodigious waste. 

Sweden, which is rich in water power, 
sends electricity across the sound to Den- 
mark. 



February, 1919 



ELECTRICAL EXPERIMENTER 



687 



Producing Rain by Electricity 

and X-Rays 



FROM time to time in the world's 
history, there have been schemes pro- 
mulgated for and attempts made at 
producing rain by artificial means 
under the control of man. One of 
the most promising of the recent schemes 
for producing rain-fall at any desired time, 
providing there happened to be aqueous par- 
ticles contained in the atmosphere, is that 
due to an Australian scientist, John Graeme 
Balsillie. He has taken out patents on his 
system of producing rain-fall electrically, 
and one of his latest American patents is 
here pictured and described. 

The illustration shows how Mr. Balsillie 
proposes to send up a series of balloons or 
large box kites of sufficient size to carry an 
extra large X-ray tube, and also capable of 
supporting two thin electric wires of con- 
siderable length. As the inventor states in 
his patent, his invention "consists in electri- 
cal means for assisting and promoting under 
suitable meteorological conditions the for- 
mation of aqueous particles in the atmos- 
phere and assisting in promoting the depo- 
sition of water particles (rain-fall) from 
the atmosphere, and further to provide suit- 
able apparatus for producing the necessary 
electrical conditions for that purpose." This 
balloon may be controlled from a motor 
truck which can speed over the country to 
various points wherever it may be de- 
sired, and a portable gasoline engine and 
dynamo outfit on the truck may supply the 
necessary current for operating the power- 
ful X-ray tube carried by the balloon, as 
shown in the illustration, and also for de- 
veloping the high potential current, about 
350,000 volts, which is employed for charg- 
ing the metallised surface of the balloon. 

As has been pointed out in previous ar- 
ticles on similar inventions in this Journal, 
— and as substantiated by the opinion of sev- 
eral well-known scientists, included Dr. 
Henryt Arctowsky, the Arctic explorer, of 
New York, — the inventor informs us in 
his patent that his discovery is susceptible 
to practical use only when the cooling of 
aqueous vapor resulting from its expansion 
in elevated regions of the atmosphere and 
other natural influences brings the vapor 
above the saturation point, so that conden- 
sation becomes possible. 

It has been ascertained that ions, pro- 
duced in this case by Mr. Balsillie by the 
powerful X-rays, which ionize the atmos- 
phere in the vicinity of the balloon, may 
act as nuclei, upon which, under certain 
conditions, water vapor will condense. 
Aqueous particles comprising cloud, fog or 
mist are invariably electrified by natural 
causes, and altho their electrification is of 
one sign, the potential or voltage distribu- 
tion thruout the mass is uneven. Aqueous 
particles of approximately equal dimensions 
and potential will therefore naturally repel 
each other, and no condensation will result. 
However, nuclei, upon which water con- 
densation may take place, can be created 
by ionizing the atmosphere, such as by pow- 
erful X-rays, and further if under normal 
conditions, a mutual repulsivity of charge 
of the aqueous particles is altered to a 
condition of mutual attractivity, then coal- 
escence of such aqueous particles will be 
assisted, and rain caused to fall. 

As the accompanying detail illustration 
shows, if a metal plate (or the metallized 
surface of the balloon) is charged at a 
very high potential of say several hundred 
thousand volts, then this electrified body 
serves to give an opposite charge to the 
aqueous particles floating in the atmosphere. 

The aqueous particles thus become pos- 



sest of a charge of opposite sign to that 
which they originally had. This charge of 
opposite sign, however, is not and cannot 
be communicated instantaneously to all the 
particles in said zone. The particles in 
close proximity to the source of electrifica- 
tion are rapidly charged by electrostatic 
mduction with a charge of opposite sign to 



whereby particles in close proximity to each 
other are possest of electrical charges of 
opposite sign. Such particles consequently 
attract each other, coalesce, and then fall 
as rain, under the influence of gravity. 

The apparatus used for producing the 
high potential uni-directional current for 
charging the metallized balloon surface is 




CopTrirtt, 1819, by B. p. Co 



Man Is Slowly But Surely Learning the How and Why of Nature's Secrets. Rain and How 
It Forms Has Particularly interested An Australian Scientist — John Graeme Balsillie, and 
His Method of ionizing and Charging the Air Containing the Aqueous Particles is Here 
illustrated and Described. Ionization Is Accompllsht By Large X-Ray Bulbs Suspended From 

Balloons. 



that which they originally possest. This 
inversion of sign of charge is gradually 
communicated to all the particles in said 
zone in an ever-expanding circle, about the 
source of electrification as a center. At the 
perimeter of the circle of imprest electrifi- 
cation, at any instant, a condition exists 



produced by a transformer and interrupter 
supplied from a dynamo or other source on 
the ground. The secondary circuit of the 
induction coil is equipt with rectifying 
valves in order to rectify the current. Sim- 
ilar appratus, also provided with vacuum 
(Continued on page 749) 



688 



ELECTRICAL EXPERIMENTER 



February. 1919 



Moving Platform for New York's Gross- 
Town Subway 



SUBWAY commuters and others who 
u^e New York's great underground 
transportation systems daily, have 
been much provoked and harast in 
the past several months by the various 
difficulties occasioned by the change in the 
two principal North and South arteries ot 
subway travel. In other words, the subway 
system was changed over a few months 
ago from the old familiar "Z" system to the 
new so-called "H" system, which gives a 
continuous east-side and west-side subway 
express route, the— bar of the "H" connect- 
inc at tlie present time by shuttle train- 
running under 42nd Street between th-. 
Grand Central Station and the Times 
Square Station. The Grand Central Sta- 
tion is located at Park .\venue and East 
42nd Street, while the Times Square Sta- 
tion is located on the west side at the 
juncture of 7th Avenue, Broadway and 
42nd Street. 

For several reasons the shuttle train 
service seems apparently not to be the best 
solution of the problem confronting the 
subway engineers in smoothly and quickly 
transferring the cross current of traffic be- 
tween these two stations, and therefore 
Public Service Commissioner Travis H. 
Whitnev has proposed that a r<))i(i'i"()i(.f 
moling' flat form such as here illustrated be 
installed in the space now ocupied by two 
of the tour shuttle tracks. Mr.-Whitney s 
original idea called for the installation of 
this continuous moving platform on the two 
noriherlv tracks of the shuttle system, leav- 
i ig the two southerly tracks for train ser- 
\ice, which might be necessitated whenever 
the moving platform might for instance get 
Oft of order, when the shuttle train service 
could be put in use. Also these two tracks 
could be used for the extension of the 
Queensboro Subway system, which is an- 
other proposal in the minds of the Public 
Service Commission engineers, so that 
eventually the Queensboro trains which 
now end their westward run at the Grand 
Central Subway Station, two levels under- 
ground as here illustrated, will terminate at 
Times Square. 

In a recent interview with Mr. M. liver- 
hart Smith, consulting engineer of the con- 
struction concern which will build this gi- 
gantic moving platform, six thousand feet 
in length and capable of carrying ten thou- 
sand people at one time, a different sug- 
gestion was made concerning the location 
of this proposed continuous moving plat- 
form. Instead of having it occupy the 
space over which the two northerly tracks 
now run, Mr. Smith pointed out that it is 
much more feasible and practical in every 
way to have it occupy the present position 
of the extreme northerly and southerly 
tracks, leaving two tracks in the center for 
emergency shuttle train service or for the 
extension of the Queensboro system to 
Times Square. This modification of the 
design and layout of the moving platform 
system is a very important one and prac- 
ticallv necessitated, for the reason that if 
the return loop of the platform past along 
in the position now occupied by one of the 
inside tracks, then passengers could not 
alight at any point desired, excepting at 
the terminal stations at either Grand Cen- 
tral or Times Square. 

As is pointed out there should be not 
less than three moving platforms in any 
case, each moving at a different speed, the 
outer one say at three miles, the inter- 
mediate at six miles, and the inner plat- 
from carrying the seats, at nine miles per 



By H. W INFIELD SECOR 

hour. Therefore, as Mr. Smith suggested, 
in discussing Mr. Whitney's original idea, 
it would not be possible for passengers 
traveling cast to attempt to cross a high 
speed (9-mile per hour) platform moving 
Zi.\'st. To give the greatest service, and to 
enalile passengers to alight from or board 
the moving platform at any point along the 
entire route, the moving platform system 
should occupy the space now used by the 
two center or the two outside tracks. In 
other words the two moving platforms 
would have to have adjacent to them a 
stationary platform provided with suitable 
exits and entrances. 

If the present shuttle train service should 
be extended to connect with other sub- 
ways on avenues farther west than 7th 
.\venue at Times Square, the trains, Mr. 
.Smith explained, would not conflict with 
the moving platforms, because the latter 
would operate only between two of the train 
stations. In this case the moving platform 
would be used merely for the collection and 
distribution of passengers within the area 
of Times Square and cast and west of it. 
Concerning the initial cost of this great 
moving platform it is estimated that it 
would approximate $1,000,000.00, and that 
it would take six months to build and in- 
stall. At the present time the engineers of 
the Public Service Commission and the 
subway staff, as well as the experts of the 
moving platform concern, are busy trying 
to find a satisfactory space for the plat- 
form return loops at the station ends at 
Times Square and Grand Central ; these 
loops being quite an extensive affair, the 
minimum diameter of the loop being about 
130 feet. 

The moving platform idea is not so en- 
tirely new or untried, as it might appear at 
first. They have been built and used at 
different times quite a number of years ago, 
both abroad and in the United States. The 
same concern which is now designing the 
one for installation under 42nd Street, had 
one in successful operation at the World's 
Fair in Chicago. 4,400 feet in length. Vis- 
itors to that Fair will undoubtedly remem- 
ber the great attraction, the platform of 
which was operated by electric motors to 
the total of 150 horsepower, which had a 
carrying capacity of 6.000 passengers. On 
"Chicago Day." 185.000 passengers— twice 
the daily traffic of the Brooklyn Bridge- 
were carried without any inconvenience. 
The total live and dead weight was 900 tons. 
.■\s aforementioned, the new platform pro- 
posal for 42nd Street. New York City, is 
approximately 6,000 feet in length, vvith a 
capacity of 10,000 passengers, and will re- 
quire electric motors distributed along its 
length to a total of about 250 horsepower. 

Undoubtedly some of our readers will be 
interested in some of the more or less ob- 
vious technical details and just how the va- 
rious parts are to operate. Thru the cour- 
tesy of Mr. M. Everhart Smith, we are 
pleased to give several details here, which 
have seemed of paramount infercst to the 
editors. First, the three moving platforms, 
moving at three gradually increasing velo- 
cities in order to allow a person to board 
it without being thrown over or requiring 
acrobatics, will not be exactly on the same 
level, but each platform will slightly overlap 
the next succeeding platform, this practise 
having been found the best from past ex- 
perience. The detailed drawings in the ac- 
companying illustrations show clearly how 
the platform is made in a large number of 
jointed sections, each of which is provided 



with a flexible coupling so as to easily nego- 
tiate the curves at the station loops. Under 
the whole moving platform there is installed 
a stationary series of wheels or pulleys 
mounted on axles. The depending rails of 
the various platforms rest on the respective 
pulleys or wheels belonging to that particu- 
lar platform in each case, as the drawing in- 
dicates. At about every eighth or tenth pulley 
there will be located a small electric motor 
connected by driving chains to several of the 
pulley shafts. All together about 250 horse- 
power in electric motors will be required, 
which is quite small indeed compared to the 
two thousand horse-power in electric mo- 
tors necessary for the operation of a ten- 
car subway train. 

The matter ot seats on the third or high- 
speed platform is a very flexible one, and • 
at first most probably but one row of seats 
will be installed, as the illustration shows, 
but more seats can readily be added at any- 
time. It will only require a few minutes to 
go from Grand Central to the Times Square 
Station or vice versa on the moving plat- 
form, and the seats would probably only be 
used by women, as Mr. Smith pointed out. 
Another feature at this point is that those 
in a hurry can walk along any one of the 
moving platforms and gain time; for in- 
stance, if a man walks at the rate of four 
miles per hour on the nine mile per hour 
platform, he will actually be moving in 
that particular direction at the rate of thir- 
teen miles per hour. In addition to the ad- 
vantages of constantly moving platforms 
with no waits for shuttle trains, and with 
entrances and exits at every cross-street, 
such as at Madison. Fifth and Sixth Ave- 
nues, an immense income could be derived 
from the stores and large advertising spaces 
along the platforms. 

Referring once more to the platform and 
its operation, it will be seen how the motor- 
driven wheels under the rails of the plat- 
form sections will cause these sections to be 
propelled forward in a direction depending 
upon the rotation of the wheels. The end- 
wise juncture between the sections and the 
moving platforms is on an even level, and 
they are closely curved on the order of a 
knuckle-joint so that no gap occurs between 
them. The rails of each section are so de- 
signed as to correspond both at front and 
back, and thus this unique design permits 
of the section moving around the loop 
curves in a smooth manner. Light steel 
posts, containing straps for the use of the 
"strap hangers' brigade," without which 
metropolitan life would lose a large part of 
its virti and pep. will be provided, as the il- 
lustration shows. Of course the chaps on 
the way home from the club will have to 
"mind their step," as the English say, or — 
well — WELL, by that time the Nation will 
he dry anyway, so we should worry!! And 
besides the late home-comers using the 
platform during the "fj. M. hours" will 
most probably be lucky enough to find it 
pretty well deserted in the event that thej- 
may have drunk one too many glasses of 
near-beer or cherry flip. 

Regarding the heating of this long tun- 
nel, Mr. Smith has suggested that during 
severe cold weather the tunnel system, in 
which the moving platform was installed, 
could be steam-heated at regular intervals, 
and also special ventilating fans and baffle 
walls could easily be provided at the various 
stations, as well as at the terminals, so as to 
ensure the proper ventilation and heating 
of the passageway. 



February. 19 19 



ELECTRICAL EXPERIMENTER 



689 




{For full description see opposite page) 



690 



IXECTRICAL EXPERIMENTER 



February, 1919 



The Unknown Purple 



WHAT would you do if you had 
the power to make yourself invis- 
ible — not by means of Aladdin's 
wonderful lamp, but by an actual 
scientific invention? Ask Dad, he 
knows! Thus, for instance, it certainly 
would be a boon to some delicately balanced 
husband, homeward bound, to escape llie 
shark eye of his better half, not to mention 



By DOROTHY K.\NT 



into a play that seems to have so big a 
success with New York's critical audiences. 

The scientist in this play who is inci- 
dentally our hero uses his invention to 
wreak vengeance upon his unfaithful wife 
and her paramour by making himself invis- 
ible and by playing pranks with the for- 
tunes of both wife and lover. 

But how docs he do it and at the same 



really concealed within the purple shaft of 
light. 

For some reason or other the authors 
seem to think that to make oneself invis- 
ible, such action should be electric and ac- 
companied by a purple liglit, in order to 
heighten the tension and to give the mys- 
terious touch that is particularly impressive 
on a lay audience. So, in addition, when- 




the rolling pin; to some suspicious wife, 
etc., etc., ad infinitum. Then think what a 
shock it would be to a Hun general, after 
the blimp observers had spied an advanc- 
ing American Army, with the guns ready 
to be set off. when whisto ! the American 
army wasn't there at all! In other words 
Grimms' Fairy Tales in real life. 

That other minds have peeped into the 
bright future of this wonderful invisible 
"source," which would make radium cheap 
by comparison, is well exemplified in the 
fact that not so long ago in the March and 
.April, 1918, numbers of the Electrical Ex- 
perimenter, in a story entitled "At War 
With the Invisible" the underlying idea of 
up-to-date scientific invisibility was shown. 
Here we had a young and handsome lady 
of the year 20H who posscst a bracelet of 
bells encircling her wrist, which bracelet 
was concealed to the human eye, or rather 
invisible to it, due to an optical invention 
of a certain scientist. . . . 

The author of the "Unknown Purple" 
evidently thought along the same lines, for 
here we have a plot with almost the same 
underlying principle, wherein a certain 
scientist discovers and perfects a sub- 
stance by which he can make himself in- 
visible merely by holding that substance in 
his hand. But let us delve a little deeper 



time raise the tension of the audience to 
such a height that you can hear a "dew" 
drop? 

One of our ingenious readers not so long 
ago wrote, jocularly, suggesting that we run 
a perfectly blank cover on the magazine 
under the caption "Camouflaged Ship on 
the Ocean". The joke was supposed to 
be that the ship was so well camouflaged 
that you could not see it at all — hence the 
blank cover page ! The authors of the 
"Unknown Purple" evidently used a simi- 
lar line of reasoning on which they built 
up their play. 

The problem was how to show a man 
walking across the stage who is supposed 
to be invisible. The answer is simplicity 
itself : don't show him at all, but make the 
audience believe that he is really there. 
This is certainly simplicity reduced ad 
ah.<!tirdtim. But in order to show that the 
man was really there, — altho, of course he 
wasn't, — something had to be done, else the 
audience would not be sufficiently imprest 
and would take the hero's "absent treat- 
ment" as a joke. So the authors simply 
have a purple spot light arranged overhead, 
which light travels at a slow gait across 
the stage, and the lighting effects are so 
cleverly arranged that the audience obtains 
the impression that the invisible man is 



ever the purple light appeared, and when 
our invisible hero was on the stage, the 
effect was still further heightened by a cer- 
tain low buzz produced by a spark coil 
vibrator or the like and which buzz was 
supposed to emanate from the substance 
in the hero's hand which created the invisi- 
bility. Needless to say it had the desired 
effect and many a young damsel felt pur- 
ple gooseskin take the place of her natural 
one, and becoming the recipient of creeps 
and thrills such as never were hers before. 
Of course, the usual stage tricks were 
resorted to, as for instance when our noble 
hero stealthily and invisibly opens the safe 
to abstract certain important papers. We 
thus see the purple spot or ray centered on 
the safe, amidst the mysterious buzzing 
sound — then the click of the combination 
as it is turned — the opening of the safe door 
slowly and mysteriously. Yes, you guest it, 
the safe was opened by invisible threads or 
strings, as no hands or anyone were visible. 
A similar trick was used whenever the hero 
entered the stage by means of the door. 
The door, of course, opened without any 
visible mechanical means and the solution 
in this case too obviously was strings or 
threads. There was only one scene that 
was staged elaborately and that was in the 
(Continued on page 748) 



February, 1919 



ELECTRICAL EXPERIMENTER 



691 



Zeppelin Flew 4,130 Miles Round Trip 
from Bulgaria to Khartoum 



BERLIN ^'NEWYORK- 

3930 MILES 
ROUND TRIP '7860 r/IIL £3 
POSilBLEBV lEPPELhyh: 



A RECENT wireless dispatch from a 
Berlin correspondenjt contains some 
most interesting news concerning 
Teutonic developments in giant air- 
craft. It is said that the Germans 
are busy constructing a mammoth airplane 
intended to cross the Atlantic Ocean. This 
huge aerial craft, now under construction, 
is stated to have a wing spread of 198 feet, 
and it is to be engined by 3,000 horse-power 
in petrol motors. 

The Teuton aerial flight experts are said 
to be busy con- 
structing a gigantic 
Zeppelin craft at 
F r i e drichshaf en, 
which is to be pro- 
pelled by nine en- 
gines and eight pro- 
pellers. It will have 
a carrying capacity of 
one hundred passen- 
gers, and it is hoped 
that the international 
situation will clear 
up so that the first 
trans - oceanic flight 
may take place this 
coming July. The 
voyage across the At- 
lantic from a point 
in Germany to New 
York City is ex- 
pected to take about 
forty hours. 

But coming down 
to cold facts and past 
performances, the ac- 
companying illustra- 
tion shows one of 
the most remarkable 
aerial trips accom- 
plisht during the 
grekt war, in which 
a giant Zeppelin flew 
from Jamboli, in 
Bulgaria, to a point 
over Khartoum, on 
the river Nile in 
Africa, a distance as 
the crow flies of 
2,065 miles, and a 
distance of 4,130 
miles for the non- 
stop return trip. The 
Zeppelin carried a 
crew of twenty-two 
men besides twenty- 
five tons of ammuni- 
tions and medicines 
for the Teuton army 
in German East 
Africa. The great 
craft glided from its 
hangar at Jamboli at 
eight o'clock on the 
morning of Novem- 
ber 21st, 1917. On 



this type was easily capable of flying from 
Berlin to New York and returning tvithout 
a stop. The air-line distance from Berlin 
to New York City is appro.ximately 3.930 
miles, and the round trip distance would be 
7,860 miles, or nearly eight thousand miles. 
Talking of dirigible gas-bag types of air- 
craft, the U. S. Navy Department has just 
announced a remarkable new gas, which is 
available by a new process. Discovery of 
this new inert, non-inflammable gas for bal- 
loons, dirigibles and other lighter-than-air 




owned by the Lone Star Gas Company, the 
statement said, and a ten-inch pipe line to 
cost $1,050,000 is being laid for a distance 
of ninety-four miles from the wells to a 
plant at North Fort Worth, where the gas 
will be comprest into cylinders for ship- 
ment to the balloon fields. 

High proof gasoline is obtained in a ratio 
of about five gallons per 1,000 cubic feet 
of gas, it was said, and after the 1 per cent 
of "argon" is removed, by agreement with 
the oil company, the remainder of the gas 
is turned into the 
city mains of Fort 
Worth and Dallas. 

The Department 
estimates that the 
plant at North Fort 
Worth, designed by 
the Navy Bureau of 
Yards and Docks, 
and which will cost 
$900,000 will be 
completed by April 1. 



RITISM 
» EAST 
AFRICA 



GERMAN 

EAST. 

AFRICA 



from the German 
ordering it to re- 



the night of Novem- 
ber 22nd -23rd, the 
monster airship had 
arrived over Khar- 
toum, when it picked 
up a wireless message 
radio station at Nauen 
turn at once, as the Government at Berlin 
had ascertained in the meantime that the 
majority of Gen. von Lettou-Worbeck's 
troops had surrendered to the Allies. 

Consequently the air-ship turned about 
in mid-air without making a landing and 
arrived at Jamboli at eight o'clock in the 
morning on November 2Sth. The technical 
director of the factory where this aerial 
craft was built has stated that a ship of 



Copyright, 1919, by E. P. Co. 

One of the Great Scientific Feats of the World-War Was the Non-Stop Flight of a German 
Zeppelin Over the Route Here Illustrated — a Distance of 4,130 Miles. Such a Craft Could 
Fly Easily From Europe to New Yorl<, and the Engineers That Built the Airship Claim 
That It Is Capable of Flying From Berlin to New York and Return, Without Stopping. 



craft was revealed by the Navy Department 
on December 9th in a statement explaining 
expenditures for its production now being 
made jointly with the army. 

The department states that the use of 
this new element, officially termed "argon," 
will eliminate the hazard of fire and explo- 
sion that always has accompanied balloon 
operations where "hydrogen" has been used 
to inflate the gas bags. 

The gas from which "argon" is obtained 
comes from the wells at Petrolia, Tex., 



INJURING THE 
EYES BY PHO- 
TOGRAPHY. 

When one sees so 
many veteran pho- 
tographic workers, 
in both amateur and 
professional ranks, 
suffering from astig- 
matism, one won- 
ders what is the 
actual cause of this 
distressing optical 
defect. On inquiry, 
it will be found that 
in many cases the 
eyes were strained 
during the early 
days of dryplate- 
photography, when 
the plates — then 
coated with a very 
slow e m u 1 s i o n — 
were handled, and 
examined during de- 
velopment, by the 
light of a deep ruby 
oil-lamp. Amateurs 
at first used advis- 
edly a small pocket- 
lamp, and undoubt- 
edly incurred serious 
injury to the sight. 
Later — thank good- 
ness — light of 
greater volume was 
employed, ruby 
light being also su- 
perseded by orange 
light : preferably 
fabric instead of 
glass being used to 
expose the dryplates 
sparingly to the rays 
of this brighter 
light. Now the pho- 
tographer confronts 
the danger of ruin- 
ing his eyes from exposure to the electric 
arc when used for printing-purposes. To 
look at the bare arc is obviously injurious 
to the sight. Arc-rays reflected from the 
surface of the negatives are also bad for 
the eyes. A good plan is to use a printing- 
lamp in which only reflected light reaches 
the negatives, or to use a printing-cabinet 
in which the arc is enclosed, care being 
taken to cover up empty spaces with pieces 
of cardboard so that the arc or its reflec- 
tions do not reach the printer's eyes. 



692 



ELECTRICAL EXPERIMENTER 



February, 1919 



Famous Scientific Illusions 



By NIKOLA TESLA 

IVritten spicially for the Electrical Experimenter 

In this original and revolutionizing discussion, Nikola Tesla gives us something really new to think about. First — Does the moon 
rotate on its axis? Second — Is the Franklin pointed lightning rod correct in theory and operation? Third — Do -wireless signals fly 
thru space by means of so-called Hertzian waves in the ether, or are they propagated thru the earth at prodigious velocity by means 

of earth-bound oscillations? World-famous conundrums these questions which have been answered in many ways by some of the 

greatest scientists. Dr. Tesla explains these three predominant scientific fallacies in a masterly way, so that everyone can understand 

them. 



THE human brain, with all its won- 
derful capabilities and power, is far 
from being a faultless apparatus. 
Most of its parts may be in perfect 
working order, but some are 
atrophied, undeveloped or missing alto- 
gether. Great men of all classes and pro- 



electric current according to a childishly 
simple rule. The writer, who was known 
to recite entire volumes by heart, has never 
been able to retain in memory and re- 
capitulate in their proper order the words 
designating the colors of the rainbow, and 
can only ascertain them after long and la- 



reality. The greatest triumphs of man 
were those in which his mind had to free 
itself from the influence of delusive ap- 
pearances. Such was the revelation of 
Buddha that self is an illusion caused by 
the persistence and continuity of mental 
images : the discovery of Copernicus that. 




It Is Well Known That the Moon, M., Always Turns the Same Face 
Toward the Earth, E. as the Black Arrows Indicate. The Parallel 
Rays From the Sun Illuminate the Moon in Its Successive Orbital 
Positions as the Unshaded Semi-circles Indicate. Bearing This in 
Mind, Do You Believe That the Moon Rotates on Its Own Axis? 



Fig. 2. — Tesla's Conception of the Rotation of the Moon, M, Around 
the Earth, E; the Moon, In This Demonstration Hypothesis, Being 
Considered as Embedded in a Solid Mass, M,. If, As Commonly 
Believed, the Moon Rotates, This Would Be Equally True For a 
Portion of the Mass M«, and the Part Common to Both Bodies 
Would Turn Simultaneously in "Opposite" Directions. 



fessions — scientists, inventors, and hard- 
headed financiers — have placed themselves 
on record with impossible theories, inopera- 
tive devices, and unrealizable schemes. It 
is doubtful that there could be found a 
single work of any one individual free of 
error. There is no 



borious thought, strange as it may seem. 
Our organs of reception, too, are defi- 
cient and deceptive. .-Xs a semblance of life 
is produced by a rapid succession of inani- 
mate pictures, so many of our perceptions 
are but trickery of the senses, devoid of 



such thing as an 
infallible brain. 
Invariably, some 
cells or fibers are 
wanting or unre- 
sponsive, with the 
result of impair- 
ing judgment, 
sense of propor- 
tion, or some 
other faculty. A 
man of genius 
eminently prac- 
tical, whose name 
is a household 
word, has wasted 
the best years of 
his life in a vis- 
ionary undertak- 
ing, h celebrated 
physicist was in- 
capable of tracing 
the direction of an 



^[iii<iifniiiiiuti:im<ti:ij u 



iiiiuiiiiiiiiiuinuiiiiiiiuiiiiiiiiiiiiuiiiiiiiiiiiiiiiiiniiiiuiiiiiiiiiniiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiumfiiiiiiiiiiiiiiiiiiiiiiiiuiiiuiiiijiiiiiiiiiiiiiiiiimiiiii^ 



FOR over a century and a half the whole world, educated and otherwise, thought that the | 

moon revolved around its axis. Nikola Tesla in the present highly instructive article dis- | 

proves that theory and will convince scientists and all others alike that the moon does | 

no such thing. | 

For thousands of years it was thought that the sun and stars revolved around the earth and ^ 

all kinds of experimental proofs were furnished to substantiate this theory. The illustrious | 

Galileo thought different, and everyone today knows that the earth revolves around the sun. | 

So it is with Tesla's discovery. Tesla also, in the second part of the present paper, shows | 

us that the ancient and time-worn theory advanced by Benjamin Franklin as to the lightning | 

conductor is not substantially correct as viewed by latter day science. It will come as a shock | 

even to our professors that the lightning rod actually aids the lightning in hitting the building. | 

The reason is that the lightning rod helps in ionizing (making conductive) the surrounding air. | 

Mr. Tesla has devised a lightning conductor with no points, and there is no doubt whatso- | 

ever that his theory is right. Scientists the world over will acknowledge this very shortly. | 

In a third section of the same paper Tesla explodes still another popular delusion, viz., that | 

wireless waves follow the curvature of the earth when messages are transmitted, let us say from f 

a point in the LJnited States to a point in Europe. In his revolutionary arguments, supported by | 

facts as well as by logic, Tesla shows why the currents do not travel around the earth but | 

directly thru it. In other words. Testa maintains that wireless communication is accomplished | 

ONLY thru the medium of the earth itself. His contention seems very sound. If it were not so, | 

let every wireless station, commercial or otherwise, do away with its ground connection. None | 

could then operate as is well known, except perhaps over very limited distances. | 

Mr. Tesla's present article will arouse world-wide comment due to the revolutionary | 

philosophy contained therein. We are sure our readers will appreciate Mr. Tesla's most timely | 

and illuminating article on this but little understood subject. | 

■ ji.!:!a:aiyjMT;:ijHirmimiiiiNniiiiniiiniiiii!'niii;i«iiiiii!iminMiiiiiiimiiiinniiiiiiiiiiiiimiiiiimiiiiniiiiiiiiiiiin»iiiNmi^ 

Copyright, 1919, by E. P. Co. All rights reserved. 



Contrary to all observation, this planet ro- 
tates around the sun; the recognition of 
Descartes that the human being is an 
automaton, governed by external influ- 
ence and the idea that the earth is spherical, 
which led Columbus to the finding of this 
continent. And 
tho the minds of 
individuals sup- 
plement one an- 
otlier and science 
and experience are 
continually elimi- 
nating fallacies 
and misconcep- 
tions, much of our 
present knowledge 
is still incomplete 
and unreliable. We 
have sophisms in 
mathematics which 
cannot be dis- 
proved. Even in 
pure reasoning, 
free of the short- 
comings of sym- 
bolic processes, 
we are often ar- 
rested by doubt 
which the strong- 



February. 1919 



ELECTRICAL EXPERIMENTER 



693 



est intelligences have been nnable to dispel. 
Experimental science itself, most positive 
of aH, is not nnfailing. 

In the following 1 shall consider three 
exceptionally interesting errors in the in- 
terpretation and application of physical phe- 
nomena which have for years dominated 
the minds of experts and men of science. 



I. The Illusion of the Axial Rota- 
tion of the Moon. 

It is well known since the discovery 
of Galileo that the moon, in travelling 
thru space, always turns the same face 
towards the earth. This is explained 
by stating that , while passing once 
around its mother-planet the lunar 
globe performs just one revolution on 
its axis. The spinning motion of a 
heavenly body must necessarily un- 
dergo modifications in the course of 
time, being either retarded by resist- 
ances internal or external, or acceler- 
ated owing to shrinkage and other 
causes. An unalterable rotational ve- 
locity thru all phases of planetary evo- 
lution is manifestly impossible. What 
wonder, then, that at this very instant 
of its long existence our satellite 
should revolve exactly so, and not 
faster or slower. Birt many astrono- 
mers have accepted as a physical fact 
that such rotation takes place. It does 
not, but only appears so; it is an il- 
lusion, a most surprising one, too. 

I will endeavor to make this clear 
by reference to Fig. 1, in which E rep- 
resents the earth and M the moon. 
The movement thru space is such that 
the arrow, firmly attached to the latter, 
always occupies the position indicated 
with reference to the earth. If one 
imagines himself as looking down on 
the orbital plane and follows the mo- 
tion he will become convinced that the 
moon does turn on its axis as it travels 
around. But in this very act the ob- 
server will have deceived himself. To 
make the delusion complete let him 
take a washer similarly marked and 
supporting it rotatably in the center, 
carry it around a stationary object, 
constantly keeping the arrow pointing 
towards the latter. Tho to his bodilv 



vision the disk will revolve on its axis, such 
movement does not exist. He can dispel 
the illusion at once by holding the washer 
fi.xedly while .uoing around. He will now 
readily see that the supposed axial rotation 
is only apparent, the impression being pro- 
duced by successive changes of position in 
space. 



"ELECTROMAGNETIC 

RADIATED HORIZON 

CONDUCTOR. SLIQHTI 

CONDUCTING EART 
^ "J ENERGY^UNIJlECOVERAeLE 



HERTZ V^/AVES-r" 
ALLY FROM VERTICAL , ,_,„,,_, 

Y AFFECTED BY I VELOCITT 

I SURFACE fSPEEPOF 



V- 
LIGHT 




y=Vcosec90°=V 



Fig. 9. THEORY. 



But more convincing proofs can be given 
that the moon does not, and cannot revolve 
on its axis. With this object in view atten- 
tion is called to Fig. 2, in which both the 
satellite, .\I, and earth, E, are shown em- 
bedded in a solid mass, Mi (indicated by 
stippling) and supposed to rotate so as to 
impart to the moon its normal translatory 
velocity. Evidently, if the lunar globe 
could rotate as commonly believed, 
this would be equally true of any other 
portion of mass Mi, as the sphere M-, 
shown in dotted lines, and then the 
part common to both bodies would 
have to turn simultaneously in oppo- 
site directions. This can be experi- 
mentally illustrated in the manner sug- 
gested by using instead of one, two 
overlapping rotatable washers, as may 
be conveniently represented by circles 
M and M:, and carrying them around 
a center as E, so that the plain and 
dotted arrows are always pointing to- 
wards the same center. No further 
argument is needed to demonstrate that 
the two gj-rations cannot co-exist or 
even be pictured in the imagination 
and reconciled in a purely abstract 
sense. 

The truth is, the so-called "axial ro- 
tation" of the moon is a phenomenon 
deceptive alike to the eye and mind 
and devoid of physical meaning. It 
has nothing in common with real mass 
revolution characterized by effects 
positive and unmistakable. Volumes 
have been written on the subject and 
many erroneous arguments advanced 
in support of the notion. Thus, it is 
reasoned, that if the planet did not 
turn on its axis it would expose the 
whole surface to terrestrial view; as 
only one-half is visible, it must re- 
volve. The first statement is true but 
the logic of the second is defective, for 
it admits of only one alternative. The 
conclusion is not justified as the same 
appearance can also be produced in 
another way. The moon does rotate, 
not on its own, but about an axis 
passing thru the center of the earth, 
the true and only one. 

The unfailing test of the spinning of 
a mass is, however, the existence of 



"ANALOGY" 




"REALIZATION 



G= PRESSURE 

INDICATOR 

GAOES 



Analogy OF Tesla's Earth Wave Vibration Theory 

EACH PULSE OF THE PUMP IS FELT WITH EQUAL 
FORCE AT ALL POINTS OF THE SPHERE. 



THE WIRELESS 
LIOHT: PLACE 
A WIRE IN THE 
ground: THAT 
IS ALL — - 




Tesla's 
wireless 
power for 
pwjpeilino 
ships and 
aeropl/ines 



Tesla's Wireless Transmission Theory, 

THE OSCILLATING ENERGY SURGES THRU THE EARTH TO 
EVERY POINT ON THE GLOBE. THUS ELECTRIC LIGHT. HEAT 
AND DOWER CAN 6E DRAWN AT ANY POINT OF THE EARTH 
FROM A UNIVERSAL CENTRAL STATION. 



Tesla's World-Wide Wireless Transmission of Electrical Signals, As Well As Light and Power, Is Here Illustrated in Theory, Analogy and 
Realization. Tesla's Experiments With 100 Foot Discharges At Potentials of Millions of Volts Have Denonstrated That the Hertz Waves 
Are Infinitesimal In Effect and Unrecoverable; the Recoverable Ground Waves of Tesia Fly "Thru the Earth". Radio Engineers Are 
Gradually Beginning to See the Light and That the Laws of Propagation Laid Down by TesIa Over a Quarter of a Century Ago Form the 

Real and True Basis of All Wireless Transmission To-Day. 



/ 



694 



ELECTRICAL EXPERIMENTER 



February, 1919 



enerey of motion. The moon is not possest tion of the latter immediately stiffens, being 
of siJch lis viva. If it were the case then a at the same time deformed by gravitational 
revolving body as'M, would contain me- pull. The shape becomes permanent upon 
chanical energy other than that of which cooling and solidification and the smaller 

f/g.S 
Highly rarefied meiiium(insulofing).- 



UtotfOTjfe/i/ rarefied conducf/r- 
atmosphere abotv insulating 

Strafum._ 




Dense fhin insulating 
layer of air 



Fig. 6 




A Section of the Earth and Us Atmospheric Envelope Drawn to Scale. It Is Obvious That the 
Hertzian Rays Cannot Traverse So Thin a Craci< Between Two Conducting Surfaces For Any 
Considerable Distance. Without Being Absorbed^ Says Dr. Tesia, In Discussing the Ether 

Space Wave Theory. 



we have experimental evidence. Irrespec- 
tive of this so exact a coincidence between 
the axial and orbital periods is, in itself, 
immensely improbable for this is not the 
permanent condition towards which the 
system is tending. Any axial rotation of a 
rriass left to itself, retarded by forces ex- 
ternal or internal, must cease. Even admit- 
ting its perfect control by tides the coinci- 
dence would still be miraculous. But when 
we remember that most of the satellites 
exhibit this peculiarity, the probability be- 
comes infinitestimal. 

Three theories have been advanced for 
the origin of the moon. According to the 
oldest suggested by the great German 
philosopher Kant, and developed by La- 
place in his monumental treatise "Me- 
canique Celeste", the planets have been 
thrown ofT from larger central masses by 
centrifugal force. Nearly forty years ago 
Prof. George H. Darwin in a masterful 
essay on tidal friction furnished mathe- 
matical proofs, deemed unrefutable, that 
the moon had separated from the earth. 
Recently this established theory has been 
attacked by Prof. T. J. I. See in a remark- 
able work on the "Evolution of the Stellar 
Systems", in which he propounds the view 
that centrifugal force was altogetlier inade- 
quate to bring about the separation and 
that all planets, including the moon, have 
come from the depths of space and have 
been captured. Still a third hypothesis of 
unknown origin exists which has been ex- 
amined and commented upon by Prof. W. 
H. Pickering in "Popular .^stronomy of 
l'X)7", and according to which the moon 
was torn from the earth when the later 
was partially solidified, this accounting for 
the continents which might not have been 
formed otherwise. 

Undoubtedly planets and satellites have 
originated in both ways and, in my opin- 
ion, it is not difficult to ascertain the char- 
acter of their birth. The following con- 
clusions can be safely drawn : 

1. A heavenly body thrown off from a 
larger one cannot rotate on its axis. The 
mass, rendered fluid by the combined ac- 
tion of heat and pressure, upon the reduc- 



mass continues to move abuut the larger 
one as tho it were rigidly connected to it 
except for pendular swings or librations 
due to varying orbital velocity. Such mo- 
tion precludes the possibility of axial rota- 
tion in the strictly physical sense. The 
moon has never spun around as is 
well demonstrated by the fact that the 
most precise measurements have failed to 



show any measurable flattening in form. 

2. If a planetary body in its orbital move- 
ment turns the same side towards the cen- 
tral mass this is a positive proof that it has 
been separated from the latter and is a true 
satellite. 

3. A planet revolving on its axis in its 
passage around another cannot have been 
thrown off from the same but must have 
been captured. 

II. The Fallacy of Franklin's Pointed 

Lightning-Rod. 
The display of atmospheric electricity has 
since ages been one of the most marvelous 
spectacles afforded to tlie sight of man. Its 
grandeur and power filled him with fear 
and superstition. For centuries he attrib- 
uted lightning to agents god-like and su- 
pernatural and its purpose in the scheme of 
this universe remained unknown to him. 
Now we have learned that the waters of 
the ocean' arc raised by the sun and main- 
tained in the atmosphere delicately sus- 
pended, that they are wafted to distant re- 
gions of the globe where electric forces 
assert iheniselves in upsetting the sensitive 
balance and causing precipitation, thus sus- 
taining all organic life. There is every 
reason to hope that man will soon be able 
to control this life-giving flow of water 
and thereby solve many pressing problems 
of his existence. 

Atmospheric electricity became of special 
scientific interest in Franklin's time. Fara- 
day had not yet announced his epochal dis- 
coveries in magnetic induction but static 
frictional machines were already generally 
used in physical laboratories. Franklin's 
powerful mind at once leaped to tlie con- 
clusion that frictional and atmosplieric elec- 
tricity were identical. To our present view 
this inference appears obvious, but in his 
. n:e ti.e mere thought of it was little short 
of blasphemy. He investigated the phe- 
nomena and argued that if they were of the 
same nature then the clouds could be 
drained of their charge exactly as the ball 
of a static machine, and in 1749 he indi- 
cated in a publisht memoir how this could 
be done by the use of pointed metal rods. 
(Continued on page 728) 



MODE OF PROPAGATION OF THE 

CURRENT FROM THE TRANSMITTER 

,\\',i;//. THRU THE EARTH 




''//'?'i?W5 



MOON'S SHADOW JUST TOUCHING; SPfSEADSOVER THE EARTH'S SURFACE 
WITH INFINITE SPEED 



PlANE OF ECLIPTIC; SHADOW 
.BaaS£5Li3y£R THE EARTH 
WITH IT'S TRUE VELOCITY 
THRU SPACE 



MOON'S SHADOW LEAVING TH 
EARTH AGAIN. REACHING INFI 
SPEED 




Fig. 8. — This Diagram 



.„ Illustrates How, During a Solar Eclipse, the Moon's Shadow 

Passes Over the Earth With Changing Velocity, and Should Be Studied In Connec- 
tion With Fig. 9. The Shadow Moves Downward With Infinite Velocity at First, 
Then WitI- Its True Velocity Thru Space, and Finally With Infinite Velocity Again. 



February. 1919 



ELECTRICAL EXPERIMENTER 



695 



G uring Soldiers Ills with Electricity 



By PAULINE BERGINS 



ELECTRICITY is playing no mean 
role in the vast reconstruction work 
now being carried on in the great 
Red Cross as well as Army and 
Navy hospitals thruout the coun- 
try. Not only has the electric current been 
cleverly employed in many diversified ways 
to treat the many ills and maladies with 
which the soldiers and sailors have been 
afflicted in this country, but thousands of 
these appliances have been and are being 
used every day in the field hospitals in 
France, and in other lands which were not 
many months ago raging battlefields. Por- 
table yet powerful X-ray ambulances sped 
over the battlefields but a few miles behind 
the front line trenches, ever ready to loan 
a helping hand in the merciful work of the 
medical corps. And not only do we find 
in these shell-torn regions the invaluable 



nervous cases caused by excessive fatigue, 
and for over-strained muscles and cords. 

There are more shell-shock victims from 
this great 
World W a r 
than there 
liave been in 
any other. And 
therefore, the 
fact that the 
Bergonie elec- 
tric chair will 
help to allevi- 
ate and cur? 
these cases, is 
indeed a great 
blessing. 

It might be 
said that the 
majority of 



of shell-shock are cured suddenly and in- 
stantly by the most peculiar incident or 
happening. In a large French hospital just 





Three Interesting Views Showing Electricity's Role In the Reconstruction 
Work of the Army Hospitals. Above: Fig. 2, Soldier Patient Receiving Elec- 
tric Arm Bath Treatment For Rheumatism, at the American Red Cross War 
Hospital at Paignton, Devon, France. Fig. 1, Below, Shows American Sol- 
dier Being Treated in the Bergonie Electric Chair, Extensively Used for 
Shell Shock Treatment, at Fort MacPherson, Ga. Fig. 3, at Left, Illustrates 
the Electric Light Bath Cabinet in Use. A Wounded Marine Is Enjoying the 
Glowing Warmth Produced By This Electrotherapeutic Apparatus For Treat- 
ing Sore and Stiffened Muscles. 



X-ray machines, but many other appliances 
such as electric heating devices for the 
treatment of "trench feet", electric steril- 
izers and cauterizers, F"aradic outfits for 
the treatment of lameness and rheumatism, 
electric light bathsf etc. 

The accompanying photographs show 
several very interesting and practical appli- 
cations of the electric current for the treat- 
ment of war ills. The photograph. Fig. 1, 
showing an American soldier seated in the 
large reclining chair, was taken at Fort 
MacPherson, Ga. This curious and com- 
plicated looking electric outfit comprises 
one of the most wonderful electro-medical 
devices ever invented^the "Bergonie" 
Electric Chair. The Bergonie invention 
involves the application of low voltage 
electric currents of peculiar wave form to 
the patient's body while seated in the chair 
here shown, the body being weighted with 
a number of sand bags. The switch-board 
in the background contains a number of 
regulating rheostats and motor-driven in- 
terrupters as well as measuring instru- 
ments, such as a voltmeter and milli- 
ampere meter for indicating the strength 
of the current applied to the patient. The 
Bergonie chair treatment produces rythmic 
pulsations in the nerves and muscles and 
has been found very efficacious for shell- 
shock victims as well as for treating severe 




shell-shock vic- 
tims lose a part 
or all of their 
mental faculties, 
and to all appear- 
ances cannot use 
their reason at 
all. They have 
all sorts of delu- 
sions as to whom 
their folks are, or 
where their .home 
is. Practically 
everyone has 
heard of, or has 
been in contact 
with, one or more 
cases of shell- 
shock, and so it 
is not necessary 
to expatiate fur- 
ther on this im- 
portant phase of 
the problem of re- 
construction, ex- 
cept to say that 
the various hos- 
pitals and sani- 
tariums engaged 
in this work are 

doing wonders over night, literally as well 
as metaphorically, for some of these cases 



Photo © by Underwood & tjnderwood 

prior to the signing of the armistice there 
(Continued on page 7A8) 



696 



ELECTRICAL EXPERIMENTER 



February, 1919 



^ kii^t^ 'J>ii ti^a '.iJ.' t!J fca im t^! iSJi iSJj MM Vi^MVUi M}iJS'!Ji}}JPKt!!MMMVi^ l}!iMJiMM ' M ^ ^ 




By Nikola Tesla 

MYFARLYLIFE 



^^^gT^ iTTi ira iTTi iTTijTTiiirrtTrsy^iiff'RiTrinr^T?'!])^^ 



t!M«wraflffgits?iisfitstiisviisnisfiiSfi:aa 



THE progressive development of man is vitally dependent 
on invention. It is the most important product of his 
creative brain. Its ultimate purpose is the complete mas- 
teo' of mind over the material world, the harnessing: of 
the forces of nature to human needs. This is the difticult 
task of the inventor who is often misunderstood and unrewarded. 
But he finds ample compensation in the 
pleasing exercises of his powers and in 
the knowledge of being one of that e.x- 
ceptionally privileged class without whom 
the race would have long ago perished in 
the bitter struggle against pitiless ele- 
ments. 

Speaking for myself, I have already 
had more than my full measure of this 
e.>cquisite enjoyment, so much that for 
many years my life was little short of 
continuous rapture. I am credited with 
being one of the hardest workers and 
perhaps I am. if thought is the equivalent 
of labor, for I have devoted to it almost 
all of my waking hours. But if work is 
interpreted to be a definite performance in 
a specified time according to a rigid rule, 
then I may be the worst of idlers. Every 
eflfort under compulsion demands a sacri- 
fice of life-energy. I never paid such a 
price. On the contrary, I have thrived on 
my thoughts. 

In attempting to give a connected and 
faithful account of my activities in this 
series of articles which will he presented 
with the assistance of the Editors of the 
El£C^^IC.^L Experime.vtf.r and are chiefly 
addrest to our young men readers, I must 




Nikola Tesla at the Age of 23. 
From An Unpublished Photograph. 



dwell, however reluctantly, on the impressions of my youth and 
the circumstances and events which have been instrumental in 
determining my career. 

Our first endeavors are purely instinctive, promptings of an 
imagination vivid and undisciplined. As we grow older reason 
asserts itself and we become more and more systematic and 
designing. But those early impulses, tho 
not immediately productive, jre of the 
greatest moment and may shape our very 
destinies. Indeed, I feel now that had 1 
understood and cultivated instead of sup- 
pressing them, I would have added sub- 
stantial value to my bequest to the world. 
But not until I had attained manhood did 
I realize that I was an inventor. 

This was due to a number of causes. 
In the first place I had a brother who 
was gifted to an extraordinarj' degree — 
one of those rare phenomena of men- 
tality which biological investigation has 
failed to explain. His premature death 
left my parents disconsolate. We owned 
a horse which had been presented to us 
by a dear friend. It was a magnificent 
animal of Arabian breed, possest of al- 
most human intelligence, and was cared 
for and petted by the whole family, hav- 
ing on one occasion saved my father's 
life under remarkable circumstances. My 
father had been called one winter night 
to perform an urgent duty and while 
crossing the mountains, infested by 
wolves, the horse became frightened and 
ran away, throwing him violently to the 
ground. It arrived home bleeding and 




Mr. Tesla at the Age of 29. 



TJOli' does the n'orltVs greatest in- 
_lj_ ventor invent? How does he 
carry out an invention? What 
sort oj mentality has Nikola Tesla? 
Was his early life as commonplace as 
most of ours? If hat tvas the early 
training of one of the World's 
Chosen? These, and many other very 
interesting questions are answered in 
an incomparable manner by Nikola 
Tesla himself in this, his first article. 
In his autobiography, treating main- 
ly on his early youth, ue obtain a 
good insight into the itonderjul life 
this man has led. It reads like a 
fairy tale, which has the advantage of 
being true. For Tesla is no common 
mortal. He has led a charmed life — 
struck down by the pest, the cholera 
and what not — given up by doctors at 
least three times as dead — ive find him 
at sixty, younger than ever. But — 
read his own words. You have never 
read the like before. 

— Editor. 

^^^^^^^^^^^^^^^^^^^^^^^^ 

Copyright. 1019. by E. P. Co. All rights reser; ed. 




Mr. Tesla at the Age of 39. 



February, 1919 



ELECTRICAL EXPERIMENTER 



by/ 



exhausted, but after the alarm was sounded immediately dashed 
off again, returning to the spot, and before the searching party 
were far on the way they were met by my father, who had 
recovered consciousness and remounted, not realizing that he had 
been lying in the snow for several hours. This horse was respon- 
sible for my brother's injuries from which he died. I witnest the 
tragic scene and altho fifty-six years have elapsed since, my visual 
impression of it has lost none of its force. The recollection of his 
attainments made every effort of mine seem dull in comparison. 

Anything I did that was creditable merely 
caused my parents to feel their loss more 
keenly. So I grew up with little confidence 
in myself. But I was far from being con- 
sidered a stupid boy, if I am to judge from 
an incident of which I have still a strong 
remembrance. One day the Aldermen were 
passing thru a street where I was at play 
with otlier boys. The oldest of these ven- 
erable gentlemen — a wealthy citizen — paused 
to give a silver piece to each of us. Com- 
ing to me he suddenly stopt and com- 
manded, "Look in my eyes." I met his 
gaze, my hand outstretched to receive the 
much valued coin, when, to my dismay, he 
said, "No, not much, you can get nothing 
from me, you are too smart." They used 
to tell a funny story about me. I had two 
old aunts with wrinkled faces, one of them 
having two teeth protruding like the tusks 
of an elephant which she buried in my 
cheek every time she kist me. Nothing 
would scare me more than the prospect of 
being hugged by these as affectionate as 
unattractive relatives. It happened that 
while being carried in my mother's arms 
they asked me who was the prettier of the 
two. After e.xamining their faces intently, 
I answered thoughtfully, pointing to one 
of them, "This here is not as ugly as the 
other." 

Then again, I was intended from my very 
birth for the clerical profession and this 
thought constantly opprest me. I longed 
to be an engineer but my father was inflex- 
ible. He was the son of an officer who 
served in the army of the Great Napoleon 
and, in common with his brother, professor 
of mathematics in a prominent institution, 
had received a military education but, sin- 
gularly enough, later embraced the clergy 
in which vocation he achieved eminence. 
He was a very erudite man, a veritable 
natural philosopher, poet and writer and 
his sermons were said to be as eloquent as 
those of Abraham a Sancta-Clara. He had 
a prodigious memory and frequently recited 
at length from works in several languages. 
He often remarked playfully that if some 
of the classics were lost he could restore 
them. His style of writing was much ad- 
mired. He penned sentences short and 
terse and was full of wit and satire. The 
humorous remarks he made were always 
peculiar and characteristic. Just to illus- 
trate, I may mention one or two instances. 
Among the help there was a cross-eyed man 
called Mane, employed to do work around the farm. He was 
chopping wood one day. As he swung the axe my father, who 
stood nearby and felt very uncomfortable, cautioned him, "For 
God's sake. Mane, do not strike at what you are looking but at 
what you intend to hit." On another occasion he was taking out 
for a drive a friend who carelessly permitted his costly fur coat 
to rub on the carriage wheel. My father reminded him of it 
saying, "Pull in your coat, you are ruining my tire." He had the 
odd habit of talking to himself and would often carry on an ani- 



NIKOLA TESLA 

THE MAN 

'By H- Gernshack 

THE door opens and out steps a tall fig- 
ure — over s.x feet high — gaunt but erect. 
It approaches slowly, stately. You be- 
come conscious at once that you are face to 
face with a personality of a high order. 
N.kola Tesla advances and shakes your 
hand with a powerful grip, surprising lor 
a man over sixty. A winning smile from 
piercing light blue-gray eyes, set in extraor- 
dinarily deep sockets, fascinates you and 
makes you feel at once at home. 

You are guided into an office immaculate 
in its orderliness. Not a speck of dust is to 
be seen. No papers litter the desk, every- 
thing just so. It reflects the man himself, 
immaculate in attire, orderly and precise in 
his every movement. Drest in a dark frock 
coat, he is entirely devoid of all jewelry. 
No ring, stickpin, or even watch-chain can 
be seen. 

Tesla speaks — a very high almost falsetto 
voice. He speaks quickly and very convinc- 
ingly. It is the man's voice chiefly which 
fascinates you. 

As he speaks you find it difficult to take 
your eyes off his own. Only when he speaks 
to others do you have a chance to study his 
head, predominant of which is a very high 
forehead with a bulge between the eyes — 
the neverfailing sign of an exceptional in- 
telligence. Then the long, well-shaped nose, 
proclaiming the scientist. 

How does this man, who has accomplished 
such a tremendous work, keep young and 
manage to surprise the world with more and 
more new inventions as he grows older? 
How does this youth of sixty, who is a pro- 
fessor of mathematics, a great mechanical 
and electrical engineer and the greatest in- 
ventor of all times, keep his physical as well 
as remarkable mental freshness? 

To begin with, Tesla, who is by birth a 
Serbian, comes from a long-lived hardy race. 
His family tree abounds with centenarians. 
Accordingly, Tesla — barring accidents — fully 
expects to be still inventing in A. D. 1960. 

But the chief reason for his perpetual 
youth is found in his gastronomical frugal- 
ity. Tesla has learned the great fundamen- 
tal truth that most people not only eat all 
of their bodily ills, but actually eat them- 
selves to death by either eating too much or 
else by food that does not agree with them. 

W^hen Tesla found out that tobacco and 
black coffee interfered with his physical well- 
being, he quit both. This is the simple daily 
menu of the great inventor: 

Breakfast: One to two pints of warm 
milk and a few eggs, prepared by himself — 
yes, he is a^bachelor! 

Lunch: None whatsoever, as a rule. 

Dinner; Celeiy or the like, soup, a single 
piece of meat or fowl, potatoes and one 
other vegetable: a glass of light wine. For 
dessert, perhaps a slice of cheese, and inva- 
riably a big raw apple. And that's all. 

Tesla is very fussy and particular about 
his food: he eats very little, but what he 
does eat must be of the very best. And he 
knows, for outside of being a great inventor 
in science he is an accomplished cook who 
has invented all sorts of savory dishes. 

His only vice is his generosity. The man 
who, by the ignorant onlooker has often 
been called an idle dreamer, has made over 
a million dollars out of his inventions — and 
spent them as quickly on new ones. But 
Tesla is an idealist of the highest order and 
to such men money itself means but little. 



mated conversation and indulge in heated argument, changing the 
tone of his voice. A casual listener might have sworn that sevcnil 
people were in the room. 

Altho I must trace to my mother's influence whatever in- 
ventiveness I possess, the training he gave me must have been 
helpful. It comprised all sorts of exercises — as, guessing one 
another's thoughts, discovering the defects of some form or ex- 
pression, repeating long sentences or performing mental calcula- 
tions. These daily lessons were intended to strengthen memory 
and reason and especially to develop the 
critical sense, and were undoubtedly very 
beneficial. 

My mother descended from one of the 
oldest families in the country and a line of 
inventors. Both her father and grandfather 
originated numerous implements for house- 
hold, agricultural and other uses. She was 
a truly great woman, of rare skill, courage 
and fortitude, who had braved the storms 
of life and past thru many a trying experi- 
ence. When she was sixteen a virulent 
pestilence swept the country. Her father 
was called away to administer the last sacra- 
ments to the dying and during his absence 
she went alone to the assistance of a neigh- 
boring family who were stricken by the 
dread disease. All of the members, five in 
number, succumbed in rapid succession. 
She bathed, clothed and laid out the bodies, 
decorating them with flowers according to 
the custom of the country and when her 
father returned he found everything ready 
for a Christian burial. My mother was 
an inventor of the first order and would, 
I believe, have achieved great things had 
she not been so remote from modern life 
and its multifold opportunities. She in- 
vented and constructed all kinds of tools 
and devices and wove the finest designs 
from thread which was spun by her. She 
even planted the seeds, raised the plants 
and separated the fibers herself. She 
worked indefatigably, from break of day 
till late at night, and most of the wearing 
apparel and furnishings of the home was 
the product of her hands. When she was 
past si-xty, her fingers were still nimble 
enough to tie three knots in an eyelash. 
There was another and still more im- 
portant reason for my late awakening. In 
my boyhood I suffered from a peculiar 
affliction due to the appearance of images, 
often accompanied by strong flashes of 
light, which marred the sight of real ob- 
jects and interfered with my thought and 
action. They were pictures of things and 
scenes which I had really seen, never of 
those I imagined. When a word was 
spoken to me the image of the object it 
designated would present itself vividly to 
my vision and sometimes I was quite un- 
able to distinguish whether what I saw 
was tangible or not. This caused me great 
discomfort and anxiety. None of the stu- 
dents of psychology or physiology whom I 
have consulted could ever explain satis- 
factorily these phenomena. They seem to have been unique altho 
I was probably predisposed as I know that my brother experienced 
a similar trouble. The theory I have formulated is that the 
images were the result of a reflex action from the brain on the 
retina under great excitation. They certainly were not hallucina- 
tions such as are produced in diseased and anguished minds, for 
in other respects I was normal ?nd composed. To give an idea 
of my distress, suppose that I had witnest a funeral or some such 
(Continued on page 743) 



698 



ELECTRICAL EXPERIMENTER 



February, 1919 



Subways of Down -Town New York 



THE down-town section of lower 
New York, including the financial or 
banking district in the vicinity of 
\Vall and Broad Streets, and other 
well-known thorofares, such as 
Broadway and the Bowling Green section, 
bids fair to become the most thoroly sub- 
waved section of any city in the world. A 
glance at the accompanying illustration. 
prepared by Mr. George Wall, a well- 
known New York artist, shows clearly 
some of the most ingenious engineering 
features connected with the gigantic sub- 
way plans which have been worked out for 
this narrow strip of land, which constitutes 
one of the most thickly populated districts 
anywhere in the world. Here office build- 
ings rise twent}- to thirty stories in the air, 
— while the heavy steel trains rumble along 
thru the bowels of the earth under these 
gigantic business structures day and night. 
Lucky for New York that it has a very 
solid rock foundation, or it is doubtful if 
all the ambitious subway and otlier arteries 
of travel now in operation and contem- 
plated, could be operated with any degree 
of safety. In preparing the accompanying 
illustration, courtesy is due to the engi- 
neers of the Public Service Commission, 
who have supplied the necessary informa- 
tion concerning the various subway routes 
here illustrated, several of which are now 
under construction and not just yet in 
eperation. 

In looking at this illustration of down- 
town New York, the well-known "battery 
loop" section is shown at the bottom, the 
top of the illustration being north, the bot- 
tom south, and the right and left — east and 
west respectively. The insert map shows 
the general plan of the subway systems in- 
cluding the Hudson Tubes under the North 
River, as well as the Pennsylvania Railroad 
Tunnels under the North and East Rivers. 
Beginning at the west side of the perspec- 
tive view we come to the new West Side 
Subway, sometimes referred to as the 7th 
Avenue Subway. This is a two-track un- 
derground railway, which runs under the 
9th .Avenue Elevated Railroad, .is becomes 
apparent. A down-town train moving 
toward the Batterj', on the West Side track, 
passes down around the loop on the outer 
or "A" track, and after it has past the Bat- 
tery Subway Station, goes down an incline 
so as to complete its loop, two levels under- 
ground, thru a tunnel which passes under 
the East Side Subway (which runs on 
Broadway in this district) and comes out 
on the up-town track running north, as the 
second arrow "A" indicates. Right here 
we have one of the most unique and clever 
bits of subway engineering imaginable, for 
this two-track system fulfills two important 
functions. 

Firstly, and as just explained, it serves as 
the return loop for the trains of the West 
Side Subway. Secondly, the inner track of 
this battery loop, or track "B," is used to 
return the local trains of the East Side 
Subway (also referred to as the old Broad- 
way Subway), and by following the inner 
or "B" track around the loop, by means of 
the dotted lines, it will be seen that the 
down-town or south-bound local train can 
complete the loop, and eventually swing 
around on to the north-bound local track. 
The two center tracks of the East Side 
Subway go to Brooklyn, and are the ex- 
press tracks. As the dotted lines convey, 
these trains dive downward two levels and 
pass thru the two westerly East River 
Tubes, one of the tubes carrying the trains 
to Brooklyn, and the other the trains re- 
turning from Brooklyn to New York. The 
East Side Subway is the older one, and the 
one that visitors are most familiar with and 
tintil recently, — when the change was made 



to the subway shuttle service between the 
Grand Central station and Times Square, 
due to the opening of the West Side Sub- 
way. — the route of the East Side Subway 
trains was northward from the Brooklyn 
Bridge terminus along Fourth Avenue, to 
Park Avenue, Grand Central station, thence 
westward under 42nd Street, then north- 
ward along Broadway, etc. .At the present 
time, owing to the change caused by the 
slnittle service put into effect between the 
(irand Central and Times Square stations, 
tliese trains make a turn to the eastward, at 
Grand Central station, and then proceed 
northward along Lexington Avenue. 

The next subway of interest is the new 
Triboro Subway, which is often referred 
to as the B. R. T. Subway, but the official 
name given to it just recently, is the Tri- 
boro Subway System. These trains will come 
from Brooklyn thru two new under-river 
tubes shown in the illustration, and proceed 
along under Whitehall Street at a depth of 
two levels, so as to pass under the East 
Side Subway, as the illustration clearly 
shows. The most southerly point of opera- 
tion at the present time, is the Whitehall 

I PUBLISHERS ANNOUNCEMENT | 

I Beginning with this issue ■ 
I the type size of ELECTRICAL 1 

m Experimenter pages is in- 1 

m creased from lo to 10^2 ■ 
B inches. This adds an equiv- B 
m (ilent of over four pages of J 
I live articles to your maga- M 
m zine, and we hope that you H 
B will welcome the improve- g 
m ment. m 

m The Publishers m 

^ lllllllllllilllllllillllllllillllllllllllllllllllllllllllllllllllllllllll 



Street station. Passengers going south 
transfer at Canal Street for Brooklyn. 
This subway passes along Church Street, 
and there is a station in the Hudson Ter- 
minal Building. Somewhat north of this, 
it makes a turn eastward and passes back 
to Broadway, and from here it runs north 
along Broadway to Times Square. At 
this point there is a station two levels 
underground with communicating passage- 
ways, so that at this interesting transfer 
station a passenger may take one of several 
subway routes, to up-town or down-town 
New York, or to Brooklyn, as well as to 
Queens, via the Queensboro Subway, which 
operates from the Grand Central Station 
under the East River, thru the Steinway 
tunnel. 

The Triboro Subway makes a turn 
north-eastward at 44th Street, and then 
runs under Seventh Avenue directly north 
to S9th Street, then proceeds eastward 
across New York at the south side of Cen- 
tral Park, and passes under the East River 
to Queens. 

Referring to the two river tubes down at 
the Battery where the Pump Station and 
Construction Shaft are shown, it is inter- 
esting to note that but two tunnels will be 
utilized at this point to take care of four 
distinct arteries of subway traffic, i.e., the 
Brooklyn-bound subway trains from the 
Triboro line, as well as those from the 
Nassau-Broad Street Subway, as the 
arrows indicate; while the other East 
River Tube takes care of New York- 
bound subway trains for the Triboro 



and Nassau-Broad Streets Subways. This 
remarkable engineering feat is taken care 
of by means of two interlocking two-way 
switches in the switch bulkheads shown at 
this point, and, of course, a very elaborate 
system of interlocking switches and signals 
has been provided in order to prevent any 
collisions, as may well be imagined. It 
must be said to the credit of the New York 
Subway System, that there have been very 
few accidents, and these were very slight, 
due to the fact that very accurate and clev- 
erly conceived electrical safety systems are 
in use, whereby one train cannot pass into 
the next "block," while it is still occupied 
by another train. 

At present the two westerly undcr-river 
tubes leading to the Triboro Subway at the 
Battery are finished and ready for use, but 
the two easterly branches are dead-ended a 
short way underground, in the vicinity of 
the Construction Shaft. 

The "Interboro" Wilham Street Subway 
will soon be completed and connects with 
the West Side Subway, running across 
town at Park Place, diving under- 
neath the East Side Subway in order to 
reach its destination. The William Street 
Subway will, pass thru the Clark Street 
Tunnel to Brooklyn (under the East River), 
and will connect with the present I. R T. 
system in Brooklyn between Borough Hall 
and Hoyt Street stations. This tunnel 
takes its name from Clark Street, Brooklyn. 

In this illustration, the several modes of 
travel available in New York City are viv- 
idly depicted by the artist, including the sur- 
face or trolley cars which run along the va- 
rious streets, as well as under the elevated 
railways. In the Battery district, here illus- 
trated, the 6th Avenue and 9th Avenue ele- 
vated roads are shown just below Rector 
Street, the 6th Avenue and 9th Avenue "L" 
lines branching into one another, and run as 
a single system down to the Battery Station. 
which is just above the Battery Subway Sta- 
tion. A similar plan is followed in the 
operation of the 2nd and 3rd Avenue "L" 
lines, as the illustration indicates. Thus 
two lines run as a single system from the 
Battery "L" Station up to a short way past 
the Brooklyn Bridge, where they branch 
out into two distinct lines of traffic. From 
this point one elevated system runs along 
2nd Avenue and the other along 3rd 
Avenue. 



WHAT IS AN ENGINEER?— ASK 
UNCLE SAM. 

Especially interesting, from the stand- 
point of the war, is the publication of a 
new definition of the engineer which has 
been written by A. H. Krom, director of 
engineering, United States Employment 
Service, Chicago. The definition comes as 
the result of the many queries that have 
originated thru a confusion of engineering 
terms and standards now in general use. 
After serious study and consultation with 
eminent, authorities, Mr. Krom prepared 
the following definition : 

"An engineer is one who economically 
directs man power and, by scientific design, 
utilizes the forces and materials of nature 
for the benefit of mankind." 

In writing this definition, Mr. Krom 
hopes to offer a practical, workable state- 
ment that will be of real value to technical 
men and to employers of technical men. 
The definition will doubtless be useful in 
clarifying popular misconceptions. Sttl- 
dents of engineering and prominent sci- 
entific authorities declare that Mr. Krom's 
definition is representative of the highest 
engineering ideals and that it covers all 
classes of engineering. In view of the im- 
portance of the engineer in the present war, 
it is highly important that his status be 
properly defined. 



February. 1919 



ELECTRICAL EXPERIMENTER 



k^Li**.! 



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(For full description see opposite page) 



700 



ELECTRICAL EXPERIMENTER 

Popular Astronomy 

THE MILKY WAY 
By ISABEL M. LEWIS 

OF THE U. S. NAVAL OBSERVATORY 



February. 1919 




Taken by Barnard with the 3.4-Inch Lens of the Bruce Tele- 
scope Temporarily Located on Mt. Wilson, Cal. This Photo- 
graph Shows the Great Star Clouds of the Milky Way in 
Sagittarius. It Is in This General Direction that the Center 
of the Entire Galactic System Is Believed to Be Located. 



THE Galaxy or Milky Way defines in 
ihe heavens the position of the fun- 
damental plane of the visible uni- 
verse and the equatorial belt of the 
celestial sphere. Our own sun. at- 
tended by its planet family, is hut one of 
the innumerable stars that stream to and 
fro m paths as yet undefined in form, but 
lying closely confined to the galactic re- 
gions and apparently controlled by the 
strong gravitational forces that exist therein. 
In fact all celestial objects, whether stars, 
nebulae or star clusters, are influenced by 
the Milky Way and as a result either crowd 
closely toward it or seek to avoid it so far 
as possible. Among the objects that par- 
ticularly favor the Galaxy are to be counted 
the helium or blue stars and the hydrogen 
or white stars. The giant red stars known 
as the tyt>e N stars are found almost exclu- 
sively here as are also the stars that appear 
to form the connecting link between stars 
and nebulae — the H'olf-Rayel stars. Here 
also are to be found all the gaseous nebulae, 
all the temporary stars, except those that 
have appeared in spiral nebulae, and all the 
loosely-forn-.cd groups or clusters of stars, 
such as the Hyades and the Ursa Major 
group, which includes Sirius and the 
brighter stars of the Big Dipper. 

The average width of this equatorial belt 
of the celestial sphere has been placed at 
approximately twelve thousand light years, 
according to most recent investigations, 
while its diameter is now known to be at 
least three-hundred thousand light years in 



extent . Out- 
side this cen- 
tral segment, 
but symmet- 
rically d i s - 
tributcdwilh 
reference to 
it, lie the 
vast com- 
pact systems 
known as 
the globular 
star clusters. 
Tho limited 
in number to 
less than one 
hundred 
they are 
composed 
i ndividually 
of t h o u - 
sands, if not 
hundreds of 
thousands, 
of stars far 
superior t o 
our own sun 
in size and 
brill iancy. 
The spiral 
nebulae, t o 
b e counted 
by numbers 
running into 
the hundreds 
of t h o u - 



sands, and 
the Greater 
and Lesser 
Magellanic 
clouds of the 
southern 
hemisphere, 
vast systems 
of stars and 
nebulosities 
resembling 
f ragments 
of the Milky 
Way in ap- 
pearance, are 
also to be 
included i n 
t h e objects 
that avoid 
the vicinity 
of the Milkv 
Way. All of 
these objects 
are charac- 
terized b y 
extremely 
high veloci- 
ties com- 
pared with 
the sluggish- 
1 y moving 
members of 
t li e Milkv 
Way. Their 
distances 
from the 
G al a X y , 
moreover, 
are incon- 
c e i V a b 1 y 
great. An 
estimate of 
the distance 



of the Lesser Magellanic cloud, and which 
is extremely reliable, places it thirty thou- 
sand light years away while the average dis- 
tance of the globular star clusters from the 
central plane of the Milky Way is more 
than Izventy thousand light years. Tho the 
distances of the spiral neljulae are still in 
doubt these objects are believed to be as 
far away on the average as the globular 
clusters. The theory has been advanced by 
Dr. Shapley of the Mt. Wilson Solar Ob- 
servatory as a result of his extensive inves- 
tigations of the globular star clusters and 
their relations to the Milky Way, that these 
vast systems and probably also the spiral 
nebulae are not found in the vicinity of the 
Milky Way because it would be impossible 
for them either to form or to exist as inde- 
pendent systems in the strong gravitational 
licld of the equatorial belt. The loosely- 
formed star clusters that are to be found 
in profusion within the Milky Way may be, 
he considers, the remnants of compact 
globular clusters that have attempted to 
cross the central plane. 

For many years it has been doubtful 
whether the numberless tiny points that 
make up the star clouds of the Milky Way 
are suns comparable in size to our own sun 
or mere star-dust, that is, fragmentary mat- 
ter of planetary rather than stellar dimen- 
sions. It is now believed that thruout the 
length and breadth of the Milky Way the 
stars average the same as they do in the im- 
mediate neighborhood of the sun. There 
are in the star clouds of the Galaxy giant 
suns that surpass our own sun hundreds 
and even thousands of times in size and 
brilliancy, and there are on the other hand, 
dwarf suns that possess only a hundredth, 
a thousandth or, in some instances, a ten- 
thousandth part of the luminosity of the 
sun. 




Star Clouds In Sagittarius. Photographed by Mr. Barnard of the Yerkes 
Observatory. This Covers a Field of About Twenty Degrees. 



February. 1919 



ELECTRICAL EXPERIMENTER 



701 



The hazy, milky light of the Galaxy is a still unknown, 
familiar feature to all who have seen it at There is no 
its best over sea or prairie on a moonless clue to the 
night of early fall, spanning the heavens in structure of 
a glorious arch of awe-inspiring beauty. the whole in 
With the aid of the most powerful tele- the infinite ya- 
scopes the nebulous background is resolved riety of its in- 
into innumerable individual points of light, tricate forma- 
each representing a star of the universe, a tions. No two 
sun attended possibly by planet-worlds of portions of 
its own. The impression one receives of the Galaxy are 
dense clouds of stars is due, it is believed, alike. There 
to the great extent of the galaxy in the is no way 
fundamental plane rather than to an actual of determin- 
crowding together of the stars. The Milky ing the rela- 
Way is known to be extremely intricate tive distances 
and irregular in form. It encircles the of the various 
heavens in the form of a great circle, but star clouds 
its width varies from twenty or thirty de- when even the 
grees in some parts of the heavens down nearest are 
to barely five degrees in others. For nearly immeasur- 
one-third of its circumference it divides ablydistant. It 
into two branches. In the constellation is the compar- 
Argo in the southern hemisphere, it sepa- atively recent 
rates into several branches crost by dark investiga- 
lanes that in one portion of its path nearly tions of the 
sever it completely. Still further south, in globular star 
the vicinity of the Southern Cross, is the clusters, which 
noted Coalsack, a huge opening in the have been 
midst of dense star clouds. The dark mark- found to be 
ings that are such a characteristic feature symmetrically 
of the Milky Way are due in some instances arranged with 
to actual breaks in the star formations reference to 
thru which it is possible to gaze into the the plane of 
immensity of space beyond, in others to the the Milky 
presence of dark absorbing matter that in- Way, thathave 
tercepts the light from the more distant furnished a 
star strata. There are numberless exam- clue to the 
pies of such dark nebulae intermingled with great extent 
vast star formations and luminous gaseous of the Galaxy 
nebulae. There are all gradations in these in the central 
dusky markings from an inky blackness to plane of the 
the greyish tinge produced by a feebly visible uni- 
glowing nebular light. The form assumed verse amount- 
by the star streams of the Milky Way is ing to a dis- 





Photographed by Barnard with the 10-Inch Lens of the Bruce 
Telescope While Temporarily Located on Mt. Wilson, Cal. 
(May 8, 1905, Exposure 3 h. 30 m.). This Photograph Shows 
About 13° of the Sky North of Theta Ophluchl. Considered 
the Most Extraordinary of All the Regions of Dark Markings 
in the Milky Way. 



Stili Another View of the Wonders of the Milky Way, 
Mr. Barnard. The White Spot at the Upper Left Is 



Photographed by 
a Small Nebula. 



tance of ap- 
proximately 
three hundred 
thousand light 
years, a value 
far greater 
than any pre- 
viously as- 
signed to ce- 
lestial dis- 
tances. Within 
six thousand 
light years of 
the central 
plane and 
fairly evenly 
d i stributed 
above and be- 
low it, are to 
be found near- 
ly all of the 
stars so far 
catalogued, in- 
cluding all 
the naked-eye 
stars and, in 
addition, all 
the irregular 
and planetary 
gaseous neb- 
ulae. 

In Fig. 1 is 
shown a sec- 
tion of the ce- 
lestial sphere 
made by a 
plane perpen- 
dicular to the 
plane of the 
Milky Way. 
The crosses 



represent the positions of some of the 
globular star clusters projected upon this 
plane. The equatorial section, A-B, is 
twelve thousand light years in width and 
three hundred thousand light years in di- 
ameter. Midway between its upper and 
lower limits lies the plane of the Milky 
Way the pole of which is at P. C marks the 
center of the entire system and the globular 
clusters are distributed symmetrically with 
reference to this point. The center of the 
black dot, S, defines the position of our 
solar system in the Milky Way. The small 
black dot has a radius of about 1,500 light 
years. Within a sphere of this radius with a 
center at the sun lie all stars and nebulae 
with parallaxes greater than two thou- 
sandths of a second of arc. Therefore 
within the black dot lie all the stars and 
nebulae, the distances of which have been 
determined by direct me^ns, that is practi- 
cally all the stars visible to the naked eye, in 
eluding such well-known stars as Capella, 
Vega, Antares, Polaris and, of course, 
Sirius and Alpha Centauri. Even the most 
massive stars of the Galaxy, thousands and 
tens of thousands of times more luminous 
than the sun, appear blended in indistinct 
milky light at the distance of C. Only the 
great telescopes break this misty light up 
into minute distinctive points of light of 
the sixteenth or seventeenth stellar magni- 
tudes. These stars form the characeristic 
star clouds of the Milky Way and it is 
readily seen from the diagram why one re- 
ceives the impression of great star density 
when gazing in the direction of C, from the 
position of the solar system at S, tho the 
actual star density may be nearly uniform 
(Continued on page 751) 



702 



ELECTRICAL EXPERIMENTER 



February. 1919 



Women Now Trained as Meter Readers 



Can women read electric meters satis- 
factorily? They can. Even when the me- 
ters are located in the darkest cellars. All 
of which has come to pass because the 
government had indicated that industries 



a certain distance and then recurve, as in 
the present case. 

Both the Army and Navy have investi- 
gated the directing of torpedoes by wireless 
from shore, and have found they can be 



tack on the steamship Antilles and on the 
destroyer Jones. 

Officials therefore are inclined to the 
belief that the Germans would not put 
any additional radio service on board a 
submarine to guide torpedoes when they 
could be directed just as well by the gy- 
roscope plan. 




.A.n electric lighting company in New 
Orleans, La., has devised a portable elec- 
tric lisbt attached to a long pole. The pole 
is puslied into the ground and the attach- 
ing cord connected to the nearest lighting 
socket. The light is used for illuminating 
gardens, tennis courts and lawn parties. 



The greater efficiency of electric cooking 
and the consequent conservation of fuel 
was pointed out in a recent article in Elek- 
tro-Technich and Maschincnhau. Cases are 
cited of bakeries in which, other factors 
being as nearly as possible identical, steam 
ovens used 0.19 to 0.21 kg. of coal per kg. 
of bread (i.e., 955 to 1,060 calories), while 
electric ovens used 0.39 to 0.42 kw-hr. per 
kg. of bread (i.e., 322 to 359 calories). The 
power consumption of the electric ovens 
was 90 kw. and 50 kw. respectively. 



Photo Chicago Commonwealth Edison Co. 



Here's a Class of Women Meter Readers Being Taught the Errors and Ways of One- 
Stepping Watt-Hour Meters. "The Hand Is Quicker Than the Eye," Says the Instructor. 

It Points to 7, but It's Only 6! What the 7X! That's Why They have a School, 

Incidentally They Are Trained How to Shoot Rats at Forty Paces. 



must help produce the needed additional 
militarj- man power, and a Chicago electric 
light company has begun to train and em- 
ploy women as meter readers. To train 
these new employees a temporary meter 
readers' school in charge of the foreman 
of meter readers has been opened. The 
equipment consists of chairs and tables, an 
exhibit of a number of meters and parts 
of meters, and a large model of a meter 
dial. This latter is used in meter reading 
practise, and examinations are held after 
the class has been thoroly instructed by 
talks accompanied by demonstrations con- 
cerning the construction and working of 
meters. Twenty or thirty changes are made 
on the large dial, each student marking 
down her record each time on a sheet of 
paper. These sheets are then collected and 
marked up by the instructor. 



given such direction. One of the inven- 
tions which attracted much attention some 
few years ago in this line was that of 
John Hays Hammond, Jr. Tests were made 
oflE Sandy Hook, and the torpedoes were 
given practically any desired direction. 

It is noted today that the case of the 
Somerstadt is not the first instance of the 
boomerang motion of a torpedo. The same 
effect was produced in the submarine at- 



SCIENCE IN THE EVOLUTION OF 
BIG GUNS AND SHELL. 

The view below shows one of the labora- 
tories at Sheffield University with a number 
of the students at that well-known English 
institution studying closely the recalescence 
of steel, or in other words, the minute mole- 
cular changes occurring in steel by means of 
the apparatus shown and which are ther- 
mally registered. 

So interesting and important is this par- 
ticular branch of scientific work, that the 
King of England, who recently visited this 
University, was particularly imprest with 
the results obtained. He manifested great 
pleasure in observing how an elaborate 
chart of the changes taking place in the 
steel under heat treatment in an adjacent 
furnace, could be registered continuously 
by a form of tape recording machiiu work- 
ing in conjunction with the split-second 
clock shown in the photograph. 



TORPEDO TURNS TO STRIKE 
SHIP. 

The case of the Norwegian steamer 
Somerstadt. which was sunk on August 
12th off Fire Island by a recurving tor- 
pedo, as stated in the official report, has 
raised the question among experts as to 
whether the Germans have not utilized the 
American invention of radio or wireless- 
directed missiles of that character. 

While there is nothing in the official re- 
port to indicate that the torpedo which 
destroyed the steamer took its eccentric 
course of passing the bow and returning 
to strike fatally on the port side by the use 
of radio power, it is not denied that such 
might be the case. 

Secretary Daniels called in an expert 
when the matter was discust at Washing- 
ton. In the latter's opinion there was 
nothing remarkable about the return of 
the torpedo. 

He explained that there were well-known 
mechanical devices, such as the gyroscope, 
by which a torpedo could be made to go 
forward from the point of departure for 




Photo© bj- O-uLrtt! .N'vws I'huUi .S.-rvlce 
An English Laboratory Which Greatly Interested the King of England. Elaborate Elec- 
tric Apparatus Enables the Observers to Record and Study the Heat Treatment of Steel 
In Adjacent Furnaces. Tape Recorders Register the Successive Changes In the Steel 

Under Treatment. 



"■B.i llffi'nsu 



February. 1919 

MT. WILSON'S HUNDRED INCH 
TELESCOPE 

By Professor Walter S. Adams, D. Sc. 

Mount Wilson Astronomical Observatory 

WITH the introduction into astron- 
omy of the instruments used in the 
physical laboratory for analyzing 
light sources and studying their brightness 
and mode of radiation, the telescope has 
come to be regarded mainly as an instru- 
ment for collecting light. The physicist to 
a certain extent has the light source at his 
control, but the light of a star is a fixt 
quantity, and the only way in which the 
astronomer can increase the brightness of 
the iinage which he desires to examine or 
to analyze is to increase the aperture of his 
telescope, say the writer in the bulletin of 
the Southern California Academy of Sci- 
ences. One instrument of tti'ice the diam- 
eter of another will collect four times as 
much light, and, will form an image of a 
star four times as bright, other things be- 
ing equal. At a period in astronomy when 
powerful spectroscopes are being employed 
for studying the motions and the chemical 
constitution of stars, and when the prob- 
lem of the structure of the universe re- 
quires that we discover and determine the 
brightness of as many as possible of the 
faintest stars in the heavens, the value of a 
great telescope is obvious. 

The project of the 100-inch reflecting tel- 
escope took form in 1906, when Mr. John 
D. Hooker provided the funds for the pur- 
chase of a suitable disk of glass, the erec- 
tion of a building for the necessary optical 
work, and the employment of skilled optic- 
ians to figure the surface of the mirror. 
In the winter of 1908 a disk was received 
from the St. Gobain Glass Company of 
France. The mirror was finally completed 
in the summer of 1916. During that pe- 
riod the work was not strictly continuous, 
it being necessary occasionally to suspend 
polishing for considerable intervals on ac- 
count of unsuitable temperature conditions. 

It is not possible here to enter into a 
(Continued on page 7SS) 



ELECTRICAL EXPERIMENTER 



703 



Largest Electric Crane 
Complete Tug-boat 

T 



Lifts 



HE world is fast beginning to realize 
that American-made goods are the 
best to be had, and, also that they are 
built on integrity, and will not col- 
lapse like the German character has 



with great accuracy. In the case of an 
accidental interruption of electric current, 
all of the crane's motions are automatically 
locked by means of brakes, and so ensures 
the impossibility of dropping the load. 





View of Mounting for Mt. Wilson's 100-Inch Reflecting Telescope. 
The Finished Mirror Weighs 4.5 Tons. The Telescope Is Floated 
on Mercury. The 600-Ton Dome Rotates Very Smoothly by Electric 

Motor. 



and the German Floating Cranes did for the 
Panama Canal. This "Made in America" 
crane is said to be the largest ever con- 
structed in this country. 

To give a more concrete idea of the 
amount of work this apparatus can accom- 
plish it may be said that its capacity is 
equivalent to the weight of 100 of the larg- 
est touring cars'. The empty lifting hooks 
weigh about two tons, 
or the equivalent of a 
large touring car. When 
the jib is raised to its 
maximum height it is 
over 200 feet above the 
water level, a height 
greater than that of an 
18-story building. As 
previously stated, the 
whole structure i s 
mounted on a flatboat, 
or floating pontoon, and 
must not be endangered 
by handling these im- 
mense loads. 

The boat contains a 
complete boiler plant, 
and an engine driven 
generator which sup- 
plies the electric cur- 
rent for operating the 
various motions of the 
crane, which are con- 
trolled from a small 
house mounted high 
above the deck. By the 
means of a few levers 
and master controllers 
one operator is able to 
control all the functions 
with the utmost deli- 
cacy. 

The speed can always 
be controlled by the 
means of the electrical 
mechanism of the 
crane. When heavy 
loads are lowered, the 
motors are turned into 
generators and thus 
the speed is controlled 



Safety and accuracy are essential, as the 
crane is used to handle large guns and 
turrets on battleships, and if thru careless- 
ness or inaccuracy these should be dam- 
aged, it wotild mean a loss of hundreds of 
thousands of dollars. 

One of the illustrations shows the first 
work which the crane did. The navy tug 
Massasoit was suddenly sunk in one of the 
harbors. After divers had past the neces- 
sary cables under the tug, the crane rapidly 
and quickly lifted it to the surface, as 
shown. 

The following data will give a good idea 
of the enormous size of this machine. Size 
of pontoon 140 feet long by 85 feet wide 
by 15 feet deep; size of engine generator 
set, ISO kw. ; the crane has a main hoist con- 
sisting of two hooks of 75 tons, each fixt 
on the jib; an auxiliary hoist of 25 tons 
capacity movable up and down on the boom ; 
the crane rotates in a complete circle, the 
rotating being controlled by two 60-h.p. 
motors ; the boom lufTs up and down from 
a practically vertical position to an agle of 
about 30 degrees from the horizontal in its 
lowest position ; the luffing is accomplisht 
by two 10-inch screws operated by two 60- 
h.p. motors ; the main hoists can operate 
separately or simultaneously, as desired ; 
when lifting the maximum load it is op- 
erated by two 60-h.p. electric motors ; the 
auxiliary hoist has separate motors for 
hoisting and trolleying, each of which is 
60-h.p. The counter-balance at the rear end 
of the crane is fixt and amounts to 600,000 
pounds ; the total weight of the pontoon 
crane (displacement) is 5,000,000 pounds; 
the capstans are electrically driven, four in 
number, one at each corner of the pontoon; 
the anchor hoists are steam driven, two in 
number, one at each end. The main pivotal 
bearing, or step bearing supports a ball or 
universal joint and carries a maximum load 
of 2,021,000 pounds; the speed of the main 
hoist under maximum load is about 6 
feet per minute ; the speed of the auxiliary 
hoist is 30 feet per minute; the speed of the 
rotation is one revolution in four minutes; 
speed of luffing boom, entire range 12 min- 
utes. The boom is of the cantilever type. 
Photos courtesy Westinghouse Electric &■ 
Manufacturing Co. 



704 



ELECTRICAL EXPERIMENTER 



February, 1919 



SELLING ELECTRICITY BY 
THE "CAN." 

WE of this generation are quite 
familiar with the method of sup- 
plying kerosene and gasoline by 
the "can," but who ever heard of 
selling electricity by the can' But 
such an arrangement promises to come into 
vogue in Chicago, where the new "meter- 
ing can" here illustrated has recentlv been 





Section and Diagram of "Metering Can": 1. 
Series Resistance. 2. Copper Leads Forming 
Part of Main Circuit, and Making Connec- 
tions with the Anode. 3. Protecting Tubes 
of Hard Rubber. 4. Solid Copper Cylinder 
Forming Part of Main Circuit, and Con- 
nected to Copper Lead at Its Upper Terminal 
by Means of Special Solder Which Melts at 
60 Degrees. 5. Copper Cylinder. 6. Copper 
Sulfate Solution. 7. Rubber Washers. 8. 
Copper Anode. 9. Shunt Resistance. 



developed and perfected. It has been pro- 
tected by United States patents issued to 
Mr. E. O. Sweitzer, of Chicago, 111., and 
the various details have been practically all 
worked out. including the design of tlic 
metering element for direct current as well 
as alternating current service. Owing to 
the abnormal conditions resulting from the 
great war, it was not deemed advisable to 
try to put this device so far on the general 

market, but now 

that peace condi- 
tions are with us, 
the concern who 
has developed this 
remarkably sim- 
ple device are get- 
ting ready to place 
it on the general 
market. This 
"metering can," as 
it may be called, 
is intended to take 
the place of the 
conventional watt- 
hour meter, or 
kilowatt - hour 
meter, especially 
for small current 
consumers, where 
it is iirstlj' — quite 
expensive to in- 
stall a watt - hour 
meter, and sec- 
ondly, — consider- 
able expense is in- 
curred on the part 
of the operating 
company, by hav- 
ing these meters 
read by profess- 
ional meter - read- 
ers every month. 

When these 
metering units 
have become avail- 
able, all Mr. 
Householder will 
hav<r to do will be 
to go to the elec- 
tric light company 
or their agents, 
and purchase sev- 
eral of these cans. 
These he takes 
home and uses 
one at a time as necessary. The ap- 
paratus works on the electrolytic principle, 
a certain amount of metal being acted upon 
by the passage of the current thru it, and 
after a certain number of hours the metal 
will have been sufficiently eaten away to 
open the circuit. 

The measurement of current depends 
upon the electrolytic action of a small cop- 
per cylinder of known weight, this being 
gradually disintegrated by electrolytic ac- 
tion during such time as the current may 
be used to light lamps or operate motors, 
etc., Imt is unaffected during the time when 
no current is being used. The electrolyte 
used either for D. C. or A. C. is a saturated 
solution of copper sulfate. These meter- 
ing cans are arranged to give a warning 
signal so that the householder will know 
ahead of time when he should replace one 
of the units with a new one. The accom- 
panying photographs show how the meter- 
ing can is plugged into a wall receptacle in 
a very simple manner. The meter can here 
illustrated is so constructed and enclosed 
in a metal case, as to remove all chances 
of tampering with it or derangement by 
accident. 

As aforementioned, the can is provided 
with a projecting contact arm which is in- 
serted in the keyhole of a switch box. It 
is then given a slight twist to engage the 
contact with the spring clips of the main 



circuit and left there until the predeter- 
mined amount of current has been con- 
sumed. Truly it may be said that this de- 
vice will mark a new era in electric service 
to the public. 



NEW ELECTRIC FURNACE 
REGULATOR. 

The device is installed easily, and when 
once in operation relieves the householder 
of all of his cares in relation to the fur- 
nace except the merely mechanical process 
of "putting on coal." The time clock ar- 
rangement makes it possible to maintain 
a low temperature during the night, and 
at the time set in the morning, opens the 
drafts and increases the temperature to the 
point desired. 

This device consists of a thermostat with 
a clock attachment which operates a motor 
in the basement, which, in turn, regulates 
the drafts and dampers of the furnace. 
Two types are provided, one for use in 
houses already wired for electricity, and 
the other in which two dry batteries sup- 
ply the impulse from the thermostat to the 
motor box, and a spring motor operates the 
drafts and dampers. 

In the type used in houses already wired 
the alternating current motor is connected 
to the alternating main house wires. A 
transformer on the bottom of the motor 
box steps the 110 volts down to 6 volts, 
for use on the thermostat circuit. Thus 
the dry batteries are dispensed with. 

Tlie diagram shows clearly how the regu- 
lator works. The thermostat may be set 
at the heat desired and it will keep the room 
in which it is installed at that temperature, 
because if the temperature falls the motor 
in the cellar will operate 
sufficiently to open the 
drafts and increase the 
heat. The reverse is true 
when the temperature rises. 
The thermostat should be 
installed in a room as near 
the center of the house as 
possible and should not be 
in such a position that its 
action is subject to the ef- 
fects of drafts from doors 
and windows opened for 
only a moment. — (Photo 
courtesy W. E. Co. 

S 3WIRe ELECTRIC 

(control Circuit 



T 





Automatic Electric Regulator Which Tends 

the Furnace Drafts for You. It Comprises 

a Thermostat, Clocl<, Motor and Battery 

or Other Sources Of Current. 



AMONG the hundreds of new devices and appliances publisht monthly in the Electrical Experimenter, there are several as a 
rule, which interest you. Full information on these subjects, as well as the name of the manufacturer, will be gladly tur- 
nisht to you, free of charge, by addressing our Technical Information Bureau. 



February, 1919 

AN ILLUMINATED SERVICE FLAG 

FOR HOME AND STORE 

WINDOWS. 

An enterprising ekctrioal concern of Mil- 
waukee is now ortering the device shown in 
the accompanying illustration, known as the 




A Handsome Window Decoration In the 
Form of an Electric-lighted Service Flag. 

"Honorlite," which is made in a form to 
take the place of a military service flag. 
The device consists of a handsorne inde- 
structible wood pulp pedestal with two 
modelled eagles holding a fiat alabaster 
globe, which is 8 inches in diameter. A 
3- by 5-inch service flag is shown on one 
face of the ball, while five blue stars are 
furnished loose and can be attached to the 
circumference or face of the ball as desired. 
This decorative device stands 12 inches 
high by tyi inches wide at the base, and is 
wired with 6 feet of cord and plug. It is 
pointed out by the maker that this device 
is one which can be used for other pur- 
poses, such as special advertising and as a 
special window display. 




ELECTRICAL EXPERIMENTER 

magnets, as always used in the convention- 
al type of magneto, this magneto employs 
straight bar magnets, which are accurately 
ground and securely clamped to top and 
bottom yokes. The bottom yoke forms a 
pole piece extending nearly half way around 
the rotor tunnel, while the top yoke has 
two poles, one carrying the windings or 
coils, and the other serving as a magnetic 
by-pass. The magnetic circuit is shown 
diagrammatically in tlie two accompanying 
sketches. In one the rotor pole is shown 
opposite the pole of a top yoke which car- 
ries the windings or coils, and with the 
rotor in this position, the maximum flux 
passes thru the coils. In the other sketch 
the rotor is shown opposite the end of the 
magnetic by-pass, and in this position all of 
the magnetic flux passes thru the by-pass 
and none thru the coils. As the rotor has 
two poles, the flux thru the coils passes 
thru a maximum and a minimum twice dur- 
ing every revolution of the rotor. 

As all coils and current carrying parts 
are stationary, there are no slip rings or 
brushes, except the brush in the distribu- 
tor. The distributor gears, of bronze and 
steel, are of ample dimensions, and in con- 
nection with the rotating member of the 
current distributor, are carried in steel and 
bronze bearings, the sleeve of which is cast 
integral with the front die casting. The 
base and top yokes are made of gray iron, 
and are tied to the die-cast end plates by 
screws. They are located in place by 
dowel pins. The field structure is bored 
'and ground as a unit, thus insuring thoroly 
accurate alignment of bearings and pole- 
faces. The stationary coil, condenser and 
laminated pole piece are assembled as a 



A NEW "INDUCTOR" TYPE 

MAGNETO FOR 

AUTOS. 

This- new auto and motor-boat ignition 
magneto is of the inductor type, which 
means that the coils in which the current is 
induced are stationary, and the revolving 
part or rotor consists merely of a block 
of laminated steel. Instead of horseshoe 



705 

Hence this machine can be used wherever 
there is electric light. 

The illumination is provided by a 14-yolt, 
2-ampere, argon-filled, high efficiency light, 
that is sufficiently brilliant for throws as 
long as 100 feet, and for pictures up to 12 
feet wide. The 110-volt current received 





VIewf of Interior of New "Inductor" Type 

Ignition Magneto. The Rotor Is Simply a 

Moving Iron (Vlember — No Rotating Colls or 

Collecting Rings. 



Diagrams Showing How the Magnetic Flux 
In the "Inductor" Magneto Is Sent Thru the 
"Coil" Pole and Then By-past Thru a "Shunt- 
ing" Pole. 

unit and mounted integral with the top 
yoke. 

This new inductor magneto gives two 
sparks per revolution. The spark charac- 
teristics are said to be such as to insure 
very effective ignition, the current rising 
suddenly to substantially its maximum value 
at the beginning, and being well sustained. 
One feathure that distinguishes the spark 
obtained from this type of magneto com- 
pared to that obtained from other magnetos, 
is that it passes thru the gap of the spark 
plugs always in the same direction. That 
is to say, the same part of the spark plug 
is always positive. 

AN ELECTRIC "MOVIE" MACHINE 
FOR THE PARLOR. 

.\ new type of moving picture machine 
for commercial, educational and home use 
has just been brought out by a New York 
concern. 

Its special features are electric motor 
drive, by a motor that can be used on both 
direct and alternating currents; high il- 
lumination, and a feed mechanism that gives 
practically perfect results. 

Motor drive was used on the older types, 
but it was necessary to have separate mo- 
tors for the different kinds of current, and 
this naturally limited the use of the motor- 
driven machines. The new motor used 
here, however, operates at practically the 
same speed with either kind of current. 




You Have Often Wisht for a Small "Movie" 
Machine for the Parlor — Here it is. Its Uni- 
versal Motor Operates on Alternating or 
Direct Current. 

from the lighting circuit is reduced to low 
voltage for the use of the lamp, by means 
of a rheostat; this rheostat is adjustable, 
so that the degree of illumination can be 
varied to suit conditions. 

The film-moving mechanism is of the in- 
termittent type and is of a novel design. 
The manufacturers claim that this pro- 
jector projects an absolutely flickerless pic- 
ture. 

This machine is safe to use since it can 
take only slow-burning films, the standard 
celluloid film being unusable in it. Many 
hundreds of these special films have already 
been made up; special subjects can be 
made up as desired, and standard films can 
be copied on to the special stock. 

The weight of the machine is 23 pounds 
and it is arranged for packing in a carrying 
case similar to a small dress suit case. 



India has increased its annual coal pro- 
duction to 12,000,000 tons and is introduc- 
ing electrical machinery into some mines. 

An electric alarm clock which awakens 
deaf sleepers by jarring their beds has been 
invented in Germany. They need it. 



A NEW ELECTRIC HORN SWITCH. 

Something new in the way of an electric 
horn switch or push button, for Ford cars, 
has been recently put on the market. It is 
attached to the throttle lever by means of 
two small clamps, and therefore is always 
within reach of the hand without an extra 
movement. 




A New and Quickly Attached 
Electric Auto Horn Switch. 



The device is a tube-shaped cylinder 
about Yi inch in diameter and 3 inches 
long, which contains contact point and 
wiring, which are cemented in place to in- 
sure durability and safety from dampness. 
The connection is made to the regular equip- 
ment by cutting in on the main wiring on 
the post. 



706 



ELECTRICAL EXPERIMENTER 



February. 1919 




^^ RADIO LEAGUE 



s^AMERICA 



HONORARY MEMBERS 

CAPT. WHG BUILARD. U S N. NIKOLA TESL A . 
PROF REGINALD FESSENDEN. DR. LEE DE FOREST. 




Manager, H Crrnshack 



Amateurs Win Question able Victory 

By H. GERNSBACK 



PYRRHUS. when congratulated by 
his friends on the occasion of his 
victory over the Romans und?r Fa- 
bricius — but which cost a terrible 
slaughter of his own men, threw up 
his hands and exclaimed: 

"Yes, but one more such victor}-, and we 
are done for !" 



attempted any nation wide movement to se- 
cure the defeat of the bill in question, save 
and only the Electrical Experimenter. 
Altho several companies manufacturing ra- 
dio instruments sent out a few thousand 
letters, no concentrated effort was made to 
appraise the entire radio fraternit>- as was 
done by this publication. About 50.000 let- 



The surprising thing however was that 
none of the other technical publications — 
there were only two of them commenting 
about the bill at all — had the situation right 
in hand. One publication which professes 
to have the interests of the amateur at 
heart did not even know that there was 
such a thing as the Padgett bill ! Not one 




You Are Wrong. 



This Is Not In Darkest 
Amateur Stall 



Prussia Where Everything Is Verboten (Forbidden), 
on A. D. 1919 When the Alexander Amendment Becomes a Law. 



CoTOTlBht, 1319. by E. P. L». 
t Merely Represents An American 



This was precisely the writer's thoughts 
when he read the amendments to the Alex- 
ander Bill, which has been under discussion 
for over a month, and which was discust 
at length in our January issue. After the 
original Alexander bill H. R. 13159 had 
been rushed into life, there were immedi- 
ately regrets by its framers, greatly ac- 
centuated by thousands of letters of pro- 
test which came pouring in upon Mr. Alex- 
ander's committee. 

Without wishing to take the credit for 
everything, it must be stated here that no 
publication, no radio club, or organization 



ters were mailed out to all radio amateurs 
interested, and the response we know has 
been nothing short of wonderful. The 
writer was in receipt of thousands of let- 
ters from amateurs, who in turn in concert 
with their friends had protested vigorously 
to Washington, with the result that the 
amendment printed elsewhere in this issue 
came about. 

Not only that, but the press was also ap- 
pealed to as well, and many papers publisht 
comments and expresf themselves in no un- 
certain language about the drastic and en- 
tirely unjustified measure known under the 
title of H.R. 13159. 



line was printed about it, and the whole 
situation was therefore more or less mis- 
handled, as all the facts had not been stated 
clearly, if at all, as they were in the January 
issue of the Electrical Experimenter, 

We wish to repeat here that if any 
change is to be made, we stand for the 
Padgett bill. It gives the amateurs ex- 
actly the same privileges as he had be- 
fore the war, and this, we know, is just 
what the amateurs want. 

Now that the situation has cleared some- 
what, we are not justified in saying that 
we think the amateur will be supprest en- 
tirely, for we know that he will not. As a 



February. 1919 

matter of fact, as things stand today we 
are not at all excited even about the amend- 
ment of the Alexander bill, for we have 
good and sufficient reasons to believe that 
the Alexander bill amended has little chance 
of l)ecom:ni; a law. 

There is no occasion or necessity for 
such a drastic measure at the present time. 
It is not justified, and if we take the prop- 
aganda which has been carried on for the 
last month in VV'ashington, the thousands 
of protest letters sent to Senators and Rep- 
resentatives, as a fair indication as to how 
the wind blows, we think we are correct in 
saying that the temper of the statesmen in 
Washington today is not such as would sup- 
port legislation of this kind at this time. 

We might write volumes why amateurs 
should not be supprest, but we believe that 
official Washington today understands the 
situation fully. They know by this time 
what service the amateurs have rendered 
their country, and how many thousands of 
expert operators were recruited into the 
Army and Navy at the outset of the war. 
Congress will surely not blot the amateurs 
out of existence in recognition of their 
work, particularly when there has not been 
advanced one single, solitary, good reason 
why the amateur should not be allowed to 
pursue his innocent endeavor. 

America, the greatest democratic country 
in the world, the one that cherishes the 
highest ideals of any nation, is not going 



ELECTRICAL EXPERIMENTER 

to start in at this late date to take away the 
liberties of hundreds of thousands of loyal 
citizens who have already proved their 
worth, and will do so again. 

In printing the amendment of the Alex- 
ander bill below, we call particular atten- 
tion to paragraph 13. This constitutes noth- 
ing but a joker, for if the bill below be- 
came a law. and if the Navy Department 
was in power, it could very readily and 
without any trouble whatsoever prohibit the 
sending of messages, let us say, between 
the hours of S P.M. to 1 A.M. This, in 
the language of the bill, would be "definite 
periods of the night or day." 

If we must have a law, let us have a law 
without "ifs" and "buts". Paragraph 13 is 
entirely too elastic in favor of the Govern- 
ment and would inevitably result in shut- 
ting the amateurs out at the slightest pre- 
text. 

There are certain things in the amend- 
ment which are undoubtedly satisfactory to 
everyone, but as a whole, we are not in 
favor of the measure. It is too autocratic, 
particularly the clause whereby it would be 
necessary for amateurs who liad receiving 
apparatus only to secure licenses. Not one 
in a hundred would wish to go to the trou- 
ble of obtaining a license for very obvious 
reasons. It has been found in the past, 
that wherever an amateur had to obtain a 
sending license, it was done most reluc- 
tantly, and it was the cause of keeping 



707 

thousands of amateurs away from wireless. 
It would work even more disastrously if 
every receiving station were to be licensed. 
Most of the jewelers — who receive time by 
wireless — and many young men would pre- 
fer not to operate their receiving stations 
for the word, "Government License", to 
many simple folk means a big undertaking, 
and in many cases when a young man iinds 
out that he must obtain a Government li- 
cense in order to have his wireless set, he 
prefers to be without it. 

What good is it anyway to license a re- 
ceiving wireless station? If a record of 
amateur stations is wanted in Washington 
why not let us insert a clause in the bill 
which would make it compulsory for every 
manufacturer or seller of radio apparatus 
to give a list of the amateurs buying such 
instruments, which to all intents and pur- 
poses would be the same thing as licensing 
and thus frightening the amateur. This 
system was in vogue during the war where 
it became necessary for all manufacturers 
to supply a list of radio sales to the Navy 
Department. 

No manufacturer would object to this, 
w-e are certain, and as the government 
would then have the list of names it would 
work out the same way without discourag- 
ing thousands of amateurs. 

The Alexander bill, amended, follows 
with our comments in parallel columns : 



Alexander Wireless Bill — Amended 

65TH CONGRESS, 3D SESSION, H. R. 13159. 

In the Sen.\te of the United States, December 11, 1918. 

Referred to the Committee on Commerce and ordered to be printed. 



AMENDMENTS. 
Intended to be proposed by Mr. 
Watson to the bill (H. R. 
13159) to further regulate 
radio communication, viz : 
On page 2, after line 8, add 
the following: 

"The word amateur, or pri- 
vate, station shall be construed 
to mean any radio station op- 
erated by a citizen of the United 



States for the benefit of himself 
and science, and which does not 
do bona fide commercial radio 
communication." 

On page 2, line 14, insert the 
words "private or amateur" be- 
fore the words "technical and 
training school stations." 

On page 2, strike out section 
3 and in lieu thereof insert the 
following: 



"First. The wave length of This is wholly satisfactory in 
private or amateur stations shall all respects. It would give the 
be from one hundred and fifty amateurs tvifcnty-five more 
meters to two hundred and meters to operate on than he has 
twenty-five meters. now. The present wireless law 

confines the amateur to 200 

meters. 



"Second. The Government 
shall have the right to stipulate 
that the power used by private 
or amateur stations shall not be 
greater than five hundred watts 
as measured in the antenna cir- 
cuit, except by special license; 
and shall not be greater than 
two hundred and fifty watts as 
measured in the antenna circuit, 
except by special license, within 
one hundred and fifty miles of 
any seacoast, lake front of the 
Great Lakes, or coast of the 
Gulf of Mexico. 

"Third. The Government shall 
have the right to prevent all per- 
sons below the age of fifteen 
years to use, operate, or own 
any sending outfit for the send- 
ing of radio disturbances into 
the ether. 



We can see no fundamental 
objection against this. 



We are wholly in accord with 
this as well. Boys under fifteen 
years of age in the past have 
made most of the trouble, and 
we believe it would be better for 
the fraternity if boys below this 
age should start in with a re- 
ceiving station to obtain pro- 
ficiency in the radio art. 



"Fourth. The Government 
shall have the right to require all 
private or amateur station op- 
erators of receiving stations to 
be licensed, and failure to pro- 
cure a license shall be punish- 
able by a fine not exceeding 
$600. 



Object most strenuously against 
this unjust measure. There is 
no necessity for licensing re- 
ceiving stations only. Our jew- 
elers, thousands of them scat- 
tered all over the country must 
have receiving stations to re- 
ceive accurate time from Arling- 
ton and the like. Not many 
would want to be licensed under 
this measure. Secrecy in wire- 
less is impossible anyway. If 
anyone must receive signals he 
can do so very readily and easily 
anyway, law or no law. Im- 
portant messages are never sent 
out by the Government or com- 
mercial companies unless they 
are in code. On top of this the 
present wireless law already has 
penalties for divulging contents 
of messages. 



"Fifth. The Government shall 
have the right to require all 
owners or operators of private 
or amateur stations to pass an 
examination whereby the op- 
erator of such station shall be 
able to receive ten words a min- 
ute before said operator may be 
licensed to operate any sending 
station. 



We see no fundamental ob- 
jection to this, except that it 
seems rather mysterious to us 
why an operator should receive 
ten words a minute. What good 
does the receiving do him. Per- 
haps the framers of the bill 
meant "send" not "receive." 



"Sixth. Private or amateur This restriction to us seems 
station operators shall not be to be too severe. We should like 
permitted to operate undamped to see 5^ K. W. inserted instead, 
sending outfits of greater ca- 
pacity than two hundred and 
fifty watts as measured in the 
antenna circuit, except by special 
license, within the territorial 
limits of the United States. 

(Continued on page 735) 



Don't fail to read a vcrv interesting discussion appearing on Page 735, entitled "Amateurs Discust Officially" by Lieut. J. S. 

Cooper, U. S. N. R. F. 



708 



ELECTRICAL EXPERIMENTER 



Feb 



ruary. 



1919 




President Wilson Always in Touch with 
Washington — via Radio 



FOR several days, going and coming 
in completing his mission to the Eu- 
ropean peace conference, it was and 
will be necessary for the President to 
administer the affairs of Government 
from the high seas. Unique as this situa- 
tion is, hardiv less so were the preparations 
made to enable him to keep in communica- 
tion with the world during the voyage. 

What is considered the most powerful 
wireless system ever installed 
on any ship is that carried by 
the steamship George IVash- 
inglon. A corner of the wire- 
less room, fitted with the new 
radio devices, the latest word 
in invention and design, is seen 
in the accompanying picture. 

Special arrangements never 
before used were made for 
handling President Wilson's 
wireless messages and to keep 
him in constant touch with 
Washington. 

This announcement was 
made by Secretary of the Navy 
Daniels in connection with a 
statement that the Navy De- 
partment was in continuous 
communication with the George 
Washington and the flagship 
Pennsylvania on their trip from 
New York. 

Means were at hand whereby 
he could be brought instantly 
into communication thru the 
powerful navy radio station at 
Annapolis, Md., and Arlington. 

Mr. Daniels said : 

The George IVashington and 
the battleship Pennsylvania are 
both equipt with the most mod- 
em radio apparatus, some of 
which was installed for this 
particular trip. 

"This apparatus includes, on 
the Pennsylvania, the most 
powerful transmitting set on 
any United States naval ship 
and also special receiving ap- 
paratus for receiving from 
high power stations used or- 
dinarily only for transatlantic 
messages. The George li'tisli- 
inglon was also especially 
equipt with similar receiving 
apparatus. On board both 
ships were installed radio tel- 
ephones and the newest type of 
low power sets for use only in 
communicating from ship to 
ship. The George Washing- 
ton and the Pennsylvania were thus able to 
communicate with each other and at the 
same time receive messages from shore. 

"All messages for the President were sent 
by the new naval high power station at An- 
napolis, which is five times as powerful as 
the Arlington station. Tnese messages were 
received by the George Washington and 
the Pennsylvania simultaneously. All re- 
plies were forwarded from the George 
Washington to the Pennsylvania and then 



instantly relayed to shore by the Pennsyl- 
vania. 

"At three special naval radio receiving 
stations, one in Maine, one in New Jersey 
and one in the Navy Building, Washington, 
expert operators listened continuously for 
the Pennsyh.'ania's messages. The mes- 
sages when received were forwarded with 
utmost despatch to the transatlantic radio 
division of the ofiice of the Director of 




Photo © by Undenvood & Underwood 

It Will Undoubtedly Be of Extreme Interest to Our Radio Readers to 
Learn That Two of the Wireless Operators Selected For Duty on the 
President's Ship— the "George Washington"— Were Formerly "Radio 
Amateurs". See Testimony As to the Worth of This Class of Men 
to the Navy Given By Lieut. Cooper Before the Committee On the 
Merchant Marine and Fisheries, Printed Elsewhere Under the "Radio 
League of America" News. 

Naval Communications in the Navy De- 
partment, and the three copies were com- 
pared to insure accuracy. The messages 
were then delivered to the addresses. All 
outgoing messages past thru the same office 
in Washington. 

"As the Presidential party approached 
Europe, by arrangement of the Navy De- 
partment, special receiving stations in both 
England and France listened for messages 
from the Pennsylvania, and one of the 



French high power stations forwarded 
messages direct to tne ship. The President 
was thus kept in touch with Washington 
and Paris or London simultaneously, for 
the George Washington easily received the 
messages sent from the Annapolis station 
until the end of the voyage and the ship 
was in Brest, France." 

The first Cabinet meeting in all history, 
directed to a certain extent by wireless 
from mid-ocean, was held in 
the White House on December 
10th, with Vice-President Mar- 
shall officiating in the Presi- 
dent's absence. 

A wireless message from the 
George Washington asked 
Vice-President Marshall if he 
would preside and the latter 
assumed his temporary duty as 
acting President. 

President Wilson was in con- 
stant communication with the 
United States and France dur- 
ing his entire voyage from the 
United States to France thru 
the U. S. S. Pennsylvania's 
powerful radio transmitting 
and receiving sets. The An- 
naoolis high power transmit- 
ting station, transmitting on 
16,900 meters, the high power 
transmitting set at New Bruns- 
wick, N. J., transmitting on 
13,000 meters, the high power 
transmitting set at Tuckerton, 
N. J., on 9,200 meters and the 
high power transmitting radio 
station in Lyons, France, on 
15,500 meters were used for 
communications to and from 
the President. 

The President on board the 
U. S. S. George Washington 
was convoyed by the U. S. S. 
Pennsylvania (which is the 
best equipt ship afloat for sig- 
nalling purposes in regard to 
radio communications) and 
five torpedo boat destroyers. 
The Pennsylvania's radio 
equipment consisted of the fol- 
lowing apparatus : One 30 
kilowatt Federal arc transmit- 
ter, which was used for trans- 
mitting messages to the United 
States and France on 3,600 
meters, one 10 kilowatt Lowen- 
stcin spark transmitter, trans- 
mitting on 600 and 952 meters, 
which was used for intermedi- 
ate communication with low 
power coastal stations ; one short range 
radio teleplione transmitter, transmitting 
on 297 meters and one vacuum tube short 
range transmitting set, transmitting on 450 
meters, which were used for intercom- 
munication between the U. S. .S. Pennsyl- 
vania and U. S. S. George Washington. 

The Pennsylvania transmitted messages 
direct to the United States up to a distance 
of 2,500 miles. Communications with 
{Continued on page 743) 



February, 1919 



ELECTRICAL EXPERIMENTER 



709 



Harvard Naval Radio Men Expert with 

Portable Sets 



THE Harvard Radio School has devel- 
oped thousands o£ expert radio opera- 
tors for the United States Naval 
Service, and a group of them are here illus- 
trated practising with one of the portable 
wireless outfits whicli landing parties use. 
It is surprising how quickly they can erect 
an aerial mast and connect the various in- 
strument cabinets together with the dy- 
namo, ready for instant service. It is all a 
matter of discipline, the commanding offi- 
cer will tell you. Discipline and system 
whereby each man does a certain thing, but 
does it well. That in a nutshell is the whole 
secret of Uncle Sam's naval efficiency. These 
men are trained to perform their duties with 
clock-like precision, and each move in erect- 
ing the wireless set here shown is done 
identically the same each time, which is the 
only way that real speed can be obtained. 
Unlike the German system, Uncle Sam's 
boys are trained not only to do a certain 
thing in a complex task and to do it well, 
but they are each and every one of them 
educated and carefully instructed on all the 
details governing the operation and func- 
tioning of the complete radio outfit. Thus 
in an emergency any one of these radio men 
can do anything from tapping the key to 
erecting the antenna, or dissembling the 
gasoline engine driving the 
dynamo, in the event that it 
fails to work, and ascertain 
just what the trouble may be. 
It has been a great task to train 
all of these thousands of radio 
operators in the various com- 
plex branches of the art, but 
Uncle Sam's radio instructors, 
both naval as well as civilian, 
have proven their worth. 



The four high 
power units which 
the company still re- 
tains include the 
Belmar-New Bruns- 
wick station in New 
Jersey, for transmis- 
sion of messages to 
England ; Chatham- 
Marion, Massachu- 
setts to Scandina- 
via; Marshall-Boli- 
nas, California to 
Hawaii ; and Koko 
Head-Kahukee, Ha- 
waii to Japan. Two 
units represent each 
station, each about 
fifty miles apart, one 
being utilized for 
transmission and the 
other for receiving. 

In taking this ac- 
tion the United 

States is merely following the lead of other 
nations in controlling the ship to shore busi- 
ness ; England took over these stations on 
her coast 12 years ago, and since that time 
they have been operated by the Postal De- 
partment. The same applies to France, 




345 MARCONI RADIO 
STATIONS BOUGHT 
BY U. S. NAVY DE- 
PARTMENT. 

All of the American Mar- 
coni radio stations, except the 
four high power plants, have 
been bought by the Navy De- 
partment, a Washington dis- 
patch of December 5th stated. 

At the same time it devel- 
oped that the department purchased the 
great Sayville station recently from the 
Alien Property Custodian along with the 
Marconi purchases. The American Mar- 
coni company relinquishes the field of hand- 
ling ship to shore messages. 

The purchase includes 45 Marconi coastal 
stations, nineteen of which are situated on 
the Atlantic and Gulf coasts, sixteen on the 
Great Lakes, and ten on the Pacific coast. 





Act 3 — Mast and Aerial Raised and Apparatus Ready For Service. 



Act 2 — Raising the Antenna M.Tst. 

Italy, Germany and countries in South 
America. Brazil has always operated her 
coast radio stations. 

An official of the company points out that 
the cream of the business in the future will 
be the transatlantic message traffic. The 
ship to shore business has never been a big 
proposition, for with the exception of a few 
ships the private business aboard ships or 
to them has never been large. At the same 
time development 
of the transatlantic 
business is going 
forward, and when 
the Government re- 
linquishes control of 
these big stations, 
they undoubtedly 
will produce big re- 
sults for the com- 
pany. 

The price paid by 
the Government is 
not announced at 
this time altho it 
has been definitely 
settled. 

The Government 
has also purchased 
from the Marconi 
Wireless Telegraph 
Company of Amer- 



A Radio Squad From the Harvard Naval Radio School Show What 

They Can Do In Rapidly Setting Up a Portable Type Radio Pack Set. 

1st Act — Unpacking the Instruments. 



ica wireless apparatus on , some 300 ships 
now under Government control. An an- 
nouncement to that eft'ect was recently 
made by Edward J. Nally, vice-president 
and general manager of the company. 
The sale of apparatus to the Government, 
Mr. Nally said, is "the first re- 
sult" of a change in the com- 
pany's policy whereby "it will 
in the future sell as well as 
lease wireless apparatus." 

A recent London dispatch 
quotes Godfrey Isaacs as say- 
ing that the Marconi Company 
would outfit airplanes employed 
in air passenger and mail ser- 
vice with wireless and would 
supply operators in the same 
way as it now serves ships. It 
also is intended to receive reg- 
ular reports of air conditions 
in different localities and to cir- 
culate these for the informa- 
tion of the pilots. As every 
airplane will have either a name 
or distinguishing number, it 
will be possible to send tele- 
grams from any part of the 
world or from any ship to an 
airplane. It is intended that this organiza- 
tion will be ready by the time the peace 
treaty is signed. 

Arrangements recently have been made 
for the erection of wireless stations in the 
extreme parts of China, one on the frontier 
of Cashmere, and another on the Chinese 
side of Siberia. Mr. Isaacs has arranged 
with Handley-Page for the transport of the 
necessaiy machinery by one or more of his 
big machines. The journey inland will take 
two or three days in place of the same 
number of months. 



NAVY MODIFIES RADIO RULES. 

Naval conditions in the North Atlantic 
are such now that restrictions upon com- 
mercial radio communications are being 
removed, according to an official announce- 
ment. Personal and commercial traffic with 
naval vessels as well as with merchant ves- 
sels is now permitted west of the 40th 
meridian. 

The restrictions upon land wire telegrams 
addrest to naval personnel on board naval 
vessels, w^hich caused such telegrams to be 
forwarded thru the Bureau of Naviga- 
tion, have "oeen removed, and it is now per- 
missible to address personal telegrams di- 
rect to men on naval vessels in an Ameri- 
ca" fort. Restrictions on a"iateur wireless 
stations have not been lifted. 



710 



ELECTRICAL EXPERIMENTER 



February. 1919 



Vacuum Valve Action and the Electric 

Current 

By K. G. ORMISTON, ASSOC, I. R. E. 

RADIO INSTRUCTOR, HEA.LD'S ENGINEERING SCHOOL, SAN FRANCISCO 



NEARLY all text-books on physics 
and electricity state that the direc- 
tion of the electric current in the 
external circuit is from the positive 
terminal of the source of pressure 
to the negative terminal. The average radio 
student, from the time he first takes up the 
study of electricity, is taught that the posi- 
tive pole of a hatteo' or dynamo is in a 
state of high pressure and the negative pole 
in a state of low pressure, and that the 




This Diagram Represents a Vacuum Valve 
Circuit. Minus the Grid Which Does Not 
Enter Into the Present Discussion. This 
Article Discusses the Direction of Current 
Flow Thru the Valve — a Mooted and Foggy 
Point to the Majority of Radio Men. Does 
the Current Pass from Filament to Plate Or 
Vice Versa? 

direction of the eletcric cur(ent is from 
positive to negative. This conventional 
theory is quite satisfactory until the vacuum 
valve and its action is considered ; then the 
confusion begins. 

Figure 1 represents a vacuum tube with 
the filament heating circuit and plate cir- 
cuit. (Tlie grid is omitted as it has no 
bearing on the present discussion.) The 
positive terminal of the battery B is neces- 
sarily connected to the plate P. In study- 
ing the action of this circuit the radio stu- 
dent i* asked to believe that the current in 
the plate circuit flows from the positive ter- 
minal of the batterj' B to the negative ter- 
minal : that is. from plate to filament within 
the tube, in spite of the fact that the ELEC- 
TRON STREAM IS FROM THE FILA- 
MENT TO THE PLATE. 

In this connection the leading text-books 
make the following statements : 

\. "Using the o/dinary convention for 
the direction of current flow (which is 
opposite to the direction of flow of the elec- 
tron stream), we say that a current flows 
from the plate to the filament." 

2. "It will prevent confusion ... if 
the student understands that inconforma- 
tion with the old theorv electricity FLOWS 
IN THE DIRECTION OPPOSITE TO 
THE FLOW OF THE ELECTRONS." 

3. ". . . the number of electrons drawn 
from F to P per second, that is, conven- 
tionally the current from P to V, is found 
. . . to be roughly proportional to the 
square of the field intensity." 

The instructors in a certain Government 
Radio School, in their efforts to "conform 
with convention," even go so far as to teach 
that positive ions flow from the battery B 
to the plate P to neutralicc the negative elec- 
trons discharged from the filament to the 
plate, and thus endeavor to show that a 
current actually flows from positive to 
negative. But these instructors fail to ex- 
plain how positive ions, .WHICH ARE 



ATOMIC IN SIZE, can flow freely thru a 
copper conductor or a vacuum ! 

It is my personal experience that much 
confusion is avoided, and a far better un- 
derstanding of vacuum valve action, as well 
as certain other phenomena, is gained if the 
radio student is taught from the start that 
the electric current is in reality a flow of 
negative charges, or electrons, from the 
negative (high potential) to the positive 
(low potential) pole of the source of 
E. M. F. 

The above statement concerning the direc- 
tion of the electric current is not a theory ; 
it is a conclusion drawn from experiment. 
That the electric current consists of a move- 
ment of ELECTRIC CHARGES can read- 
ily be shown by the following simple ex- 
periment* 

In Figure 2, P is an insulated metal plate. 
G is a sensitive D'Arsonval galvanometer, 
connected between the plate and the earth. 
The simple cell ZC and key K are con- 
nected as shown, with the zinc or negative 
terminal of the cell connected to the same 
side of the galvanometer as the metal 
plate P. R is a niitta-percha rod, which is 
held in the hand and may be electrified by 
rubbing with cat's-fur. The gutta-percha 
rod when subjected to friction becomes 
negatively charged. When the charged rod 
is moved near the plate P, the galvanometer 
will deflect in a certain direction, let us say 
to the right. The deflection of the galva- 
nometer is caused by an electric current 
passing thru its windings, and the current 
must consist of a flow of electric charges. 
Negative charges may be repelled from the 
plate by the presence of the negatively 
charged rod, and flow thru the galvanom- 
eter to the earth, or positive charges may 
be attracted from the earth and flow to the 
plate. . In either case, it is the flow of elec- , 
trie charges which produces the effect of 
an electric current. As would be expected, 
when the charged rod is removed the gal- 
vanometer deflects in thre opposite direction, 
that is. to the left. The removal of the rod 
either allows the negative charges which 
were driven from the plate to the earth," to 
return to the plate, or releases the excess 
of positive charges which had been attracted 
to the plate and they pass off to the earth. 
During the first part of the experiment 
the key K has remained open. Now place 
a heavy shunt on the galvanometer, so the 
current from the simple cell cannot dam- 
age the instrument. Then close the key 
K. The galvanometer will deflect TO THE 
RIGHT. Note that the deflection is in the 
same direction as when the charged rod 
was made to approach the plate P, and 
therefore cither negative charges are flow- 
ing thru the galvanometer from A to B or 
positive charges from B to A. We can now 
draw this conclusion : The electric cur- 
rent consists of either a stream of nega- 
tive charges flowing from the negative ter- 
minal to the positive terminal, or a stream 
of positive charges flowing from positive 
to negative, or possibly both. 

The smallest possible electric charges, 
both positive and negative, have been iso- 
lated in experiments by J. J. Thompson 
and other scientists, and their mass and 
velocity are definitely known. The smallest 
charge is negative in sign, that is, it shows 

• Ail students in elementary electricity at the 
Los Angeles Polytechnic High School are required 
to perform this experiment. See "Elementary 
Electricity," by Prof. H. LaV Twining. 



the same characteristics as a gutta-percha 
rod when electrified ; is approximately 
l/18(X)th the size of the smallest atom 
(hydrogen), and is called the "Electron." 
The smallest positive charge is found in 
the atom which has lost one or inore elec- 
trons, and is therefore atomic in size. This 
smallest positive charge, which is but an 
atom deficient in negative electricity, is 
called an "Ion." 




Experimental Circuit V\/hich Students Are 
Trained to Learn the Actions of and Which 
Proves the Audlon Explanation Here Set 
Forth. G is a Sensitive Galvanometer. Z-C a 
Simple Battery Cell, K Represents a Key, E 
the Earth Connection, P a Metal Plate, R a 
Gutta Percha Rod, Which Can Be Electrified. 

It iii evident that the positive ion cannot 
act as a carrier of electricity in a solid 
medium, or in a vacuum, on account of its 
size which must he at least as large as the 
smallest atom. But the electron, bearing 
the negative charge, can easily pass between 
the atoms of a solid conductor. 

From the experiment of Figure 2, we 
concluded that the so-called electric cur- 
rent consists of a stream of electric charg^. 
either positive or negative. Thompson^; 
measurements show that the posilive charge 
cannot flow (in ihe media with which we 
are dealing) ; therefore, we may state that 
the electric current is a movement of elec- 
trons (negative charges') from the nega- 
tive pole of the source of pressure to the 
positive pole. 

For further proof let us again consider 
the vacuum tube circuit of Figure 1. We 
have a circuit connected to the battery B, 
made up of copper conductors and the 
space F — P, which is devoid of all matter. 
The ammeter A indicates that an electric 
current flows in this circuit. Since no pon- 
derable matter exists in the vacuum tube, 
the only possible carriers of electric charges 
within the tubes are electrons. The fila- 
ment F is heated to incandescence in order 
that ionization will take place, and elec- 
trons will be emitted from it. It is neces- 
sary, in order to have any current at all 
in the pla,te circuit, that the positive pole 
of the battery P> be connected to the plate 
P, so that the negative charges (electrons) 
will be attracted to the plate rather than re- 
pelled from it. With the arrangement of 
Figure 1 there will be a stream of elec- 
trons or negative charges flowing from F 
to P within the tube, and it follows that 
the current in the plate circuit indicated by 
ammeter A must consist of a movement 
of electrons from the NEGATIVE pole of 
battery B to the POSITIVE pole. 

Let us not be hampered by "convention" 
and "old theories," but endeavor to seek the 
Truth. Then Progress will be assured. 



February. 1919 



ELECTRICAL EXPERIMENTER 



711 



THREE GOOD "HOOK-UPS" FOR A 
SMALL RECEIVING SET. 
Four instruments are needed for thii 
simple receiving set, and all are of the 
"P., I. Co." make. They are. one small 
tuning coil, one Miniature detector, one 




Here Are Three Simple, Yet Very Effective 

Hool<-ups for a Smaii Wireless Receiving 

Set. Which Is Equipt with a Tuning Coll. 

Condenser. 'Phone and Mineral Detector. 

&xt condenser and one Pony telephone re- 
ceiver. In the diagrams, which are self- 
explanatorj', A is the Aerial ; G the Ground ; 
T.C. the Tuning Coil; M.D.— Miniature 
detector ; F.C. — -fixt condenser and PR. — 
Pony receiver. With a suitable aerial and 
ground system, you will be. surprised bv 
the good vifork this little set will do. Il 
is interesting to try the different "HooE- 
Ups" to find which works best in your 
locality. 
Contributed by FRED FLOYD, JR. 



HOW TO LEARN THE INT'N'T'L 
CODE ABBREVIATIONS. 

The attached drawing is that of a rotat- 
ing dial to be used in quickly ascertaining 
the definition of the various International 
Radiotelegraphic Abbreviations. Such as: 




QRA? What ship or coast station is that? 
USA? Are my signals strong? 

As shown in the drawing the bottom or 
larger disc is made stationary to a wooden 
base and upon it the various definitions are 
printed above the QR's and below the 
US's, so that when the smaller disc, firmly 
held by the rod holding the handle, is 
rotated in alignment with the letters of the 
alphabet, the definitions are indicated thru 
the slot cut in the rotating disc. 

Contributed by E. T. J. 



EFFICIENT GALENA DETECTOR. 

Everyone is sure to have a small piece of 
brass rod for which he can find no use. 
The hard rubber top to an ink bottle in 
connection with a brass cap from an old 
dry cell forms a cup. A garage will give 
you all the slightly worn ball bearings you 
can use and you need but two. If you have 
never broken a ruler with a brass strip in it 
you are a wonder. A few screws, a nut, a 
couple of binding posts and a piece of 
board or fiber and you have the makings of 
a good detector. The accompanying illus- 
tration tells the rest. Once you have the 
tension screw, all you do is hook her up 



Clever Dial Scheme for Use In Quickly Ascer- 
taining the Definition of the Various Inter- 
national Radio Abbreviations, Such as 
Q R A7— Q S A?, etc. 



Tens/on screw ga/i 
& 




A Real "Ball-Bearing" Detector — "Radio- 
bugs." The Cup Swivels Nicely, While the 
Cat-Whistcer Arm Is Balanced — a Design 
in Great Favor by Experts. 

and with a second's adjustment (.which 
won't knock out) in come the signals fine 
and clear. 
Contributed by H. C. BENEDICT. JR. 



NOVEL BUZZER PRACTISE SET. 

In the' drawing (A) is a key of any 
type, mounted o^i a board as shown. (B) 
is a buzzer of high pitch. (C) is a coil of 




Unique Buzzer Practise Circuit in Which the 

'Phones Are Shunted Across a Resistance 

Coil, in Series with the Buzzer. 

wire which is wound non-inductive; an in- 
ductive coil will not work. This coil may 
be made by using 50 feet of No. 24 insu- 
lated wire, doubling it and winding it 
double, starting with the loop end. Why 
this is done need not be explained here. 
(D) are the battery binding posts, and (E) 
are for the phones. A 75 ohm receiver 
will work fine. 
Contributed by M. ABRAH.\M. 

A HANDY ADJUSTABLE CONDEN- 
SER. 
The feature of this condenser is that the 
capacit\' tmits are stationary and therefore 



least apt to get out of order ; the switch 
element only rotates. The builder can 
make the condenser of any size desired. 
The case is made of hardwood, sandpapered 
and varnished in the usual way. This con- 





ciiLiHiHn 



u{ini^>^^- 



s::;:s^as:p^ 



inde* aHached to switch btade 



I i ■! 



Cdptact po/nfs 




■Scale 



An Adjustable Condenser Suitable for Use in 
Radio or Spark-Coil Primary and Other Cir- 
cuits. The Switch Is of the Accumulative 
or Integrating Type. 

denser has been found suitable for every 
kind of work where an adjustable capacity 
is employed. The scale is read thru an 
index window attached to the moving 
switch blade. 
Contributed by H. B. MASSINGILL. 



DEAD-END SWITCH. 

The ends of coil units are brought to 
switch points, oife on each end of wire, (1, 
2, 3; 4, 5, 6, 7). Note the fiber or other in- 
sulated plate, carrying at the under 
edge brass strips (C) which, when disc is 
turned (by knob B) connects the switch 
p lints over which the strips lie. D is a 
brass strip which makes contact only with 



\7 

WAANW\ 



Coil sections 

I AAAA A/W\ AMA 




Fiber 



Dead-End Switches Are a Practical Neces- 
sity Nowadays On All Radio Receptors. 

outside row of points. Suppose (D) were 
on point 5. Then the pairs 1, 2, 3 and 4 
would be connected, but 6 and 7 would be 
entirely out of circuit, because (D) touches 
only the outside switch point. D connects 
to crouiid. 
Contributed by HERBERT RICHTER. 



712 



ELECTRICAL EXPERIMENTER 



February, 1919 




HUCTnffl 




The Vortex Ring Theory of the Electron 

By F. W. RUSSELL and J. L. CLIFFORD 



THE discussion of the various theories 
oi matter is one of the most im- 
portant problems that confront the 
scientist today. Chemistry', Physics, 
and nearly all branches of science 
hinge upon this question. The atomic 
theory has been thoroly establisht, but 



ing. They claim that the electron is noth- 
ing more or less than a minute whorl in the 
ether, or as we shall call it an ether vortex 
ring. 

\V hen Lord Kelvin brought forward 
about 1870 his famous vortex ring theory 
of the atom, the scientific world hailed with 




A Most Beautiful Laboratory Experiment Is that of the "Vortex Ring". With the Simply Constructed Appa- 
ratus Here Illustrated Vortex Rings of Various Sizes and Kinds Can Be Set Up At Will, By Means of the 
Red Liquid "Gun" At the Left of the Tank, Various Colors of Rings Can Be Made with Different Solutions. 
I The "GJn" Is Actuated By an Electric Bell Movement, Minus the Gong. 



the ultimate structure of the atoms is still 
an open question. The leading theories of 
today make use of smaller particles called 
electrons to form their hypothetical atoms. 
These particles were first discovered by 
Crookes, and about 1897 were definitely 
proved by Weichert, and Sir J. J. Thom- 
son, to be nega'iively charged particles 
traveling with the enormous velocity of 
nearly 100,000 miles per second. In addi- 
tion it was found that these particles had 
an extremely small mass. In fact about 
one eighteen-hundredth the mass of an 
hydrogen atom, the smallest known atom. 
The presence of these particles was again 
proved by the disintegration of Radium, 
and even an electric current is now believed 
to be a flow of these electrons. The elec- 
tron then is one of the most important 
entities in the world today, and yet there 
are very few theories as to the nature of 
the electron. The physicist has side-stept 
the problem in the past by simply calling it 
a hard negatively charged corpuscle, but 
what a hard corpuscle is, is left to the 
reader's imagination to picture. Lately, 
however, the new school of French physi- 
cists have brought forward the theory 
which seems most complete and astound- 



delight this tangible explanation of the 
structure of the atom. Upon the discovery 
of the electron, however, the vortex atom 
theory was thrown into the background 
and into obscurity. Since the new theory of 
the electron has been proposed; however, it 
is interesting to repeat and 
discuss the experiments 
with smoke and liquid 
rings performed by the ex- 
perimenters wishing to 
prove the vortex atom 
theory. 

The simplest form of ap- 
paratus needed to produce 
rings of smoke is a round 
cardboard box with a small 
aperture in one end. If 
the box is filled with 
smoke or with fumes of 
Ammonium Chlorid 
formed by the action of 
Ammonia and Hydrochlo- 
ric .Acid, and the opposite 
end tapt sharply, rinp^ 
of smoke will be projected 
from the box and will hold 
their shape for some time. 
The rings move swiftly 
forward, carrying with 



them the same material with which they 
issued from the box, and seemingly possess 
elasticity of form. Altho many interesting 
phenomena may be observed using this sim- 
ple form of apparatus, for accurate and 
detailed experiment the liquid ring appa- 
ratus, described below, will be found the 
more practicable. 

The first requisite is a 
glass tank at least 30 
inches long by 12 inches 
wide and high. A gold 
fish aquarium will answer 
the purpose, provided it 
conforms to the dimen- 
sions. If an aquarium is 
not available, a tank may 
be easily constructed by 
inaking a box with the 
base of wood and the sides 
of glass plates. This box 
should be well coated with 
asphaltum in order to 
make it water tight. When 
the experimenter has pro- 
vided himself with a suit- 
able tank, the next prob- 
lem which confronts him 
is the construction of the 
"gun" or projector with 
which to generate the vor- 
tex rings. An efficient gun 
may be easily manufac- 
tured from odds and ends 
to be found in any ex- 
perimenter's laboratory. As 
may be seen in the draw- 
ing. Fig. 1, the two prin- " 
cipal parts of the gun are 
the liquid container and 
the electric agitator. At 
one end of the liquid con- 
tainer, which consists of 
a round tin box, is fast- 
ened a diafram of 
Phosphor-Bronze sheet or other flexible 
substance. In the opposite end, which may 
be the cover to the box, a small hole 
about Vi» of an inch is cut, care being taken 
that the sides of the hole are smooth in 
order to insure perfectly formed rings. 




Here We See the Actual Vortex Ring Apparatus Set Up in the 
Authors' Laboratory. 



February, 1919 



ELECTRICAL EXPERIMENTER 



713 



The box should be made water tight. As 
may be seen in the drawing the agitator 
consists of a strong electric bell with the 
gong removed, and the leads taken directly 
from the coils. The bell should be well 
impregnated in parafiine or other insulating 
compound so that it may be submerged 
without danger of short circuit. The bell 
should be so placed that the striker will 
strike the center of the diafram a force- 
ful blow when the magnets are energized. 
The best position for the striker can only 
be determined by actual experiment. 

When the projector has been completed, 
if the experimenter wishes to use red col- 
ored rings, the liquid container should be 
filled with a solution of Sodium Hydroxid, 
and Phenolphthalein. Be sure that all the 
air has been expelled, as any air in the 
container causes the rings to be irregular. 
The gun is then lowered into the tank, and 
the magnets energized by means of bat- 
teries, controlled by a telegraph key. Rings 
will be seen to issue from the aperture, 
and traverse the length of the tank intact. 
If the water is ^slightly acidulated with 
Sulfuric Acid the rings will immediately 
disappear upon breaking up. If the ex- 
perimenter wishes to make milk-white 
rings, an emulsion of Silver Chlorid can 
be used that will become colorless in ^ 
weak solution of Ammonia. To make such 
an emulsion a tablespoonfuU of gelatin 
should be dissolved in about a liter of hot 
water. About 15 grams of Silver Nitrat 
previously dissolved in water should be 
added. Then stirring well, add a weak so- 
lution of Hydrochloric Acid until the Ni- 
trat is all precipitated as a chlorid. This 
milk-white solution should be diluted with 
equal parts of water before using. Rings 
of this solution shot out into a weak solu- 
tion of Ammonia, will hold their form until 
broken, and will then completely disap- 
pear. The amount of current necessary 
for each gun can only be determined by 
practice, and the nature of the rings wished. 
After some practice, the key can be so 
manipulated as to produce swiftly, or 
slowly moving rings. Two guns should 
be constructed, as it is necessary in some 
experiments to connect them in series, and 
shoot rings towards each other. The guns 
should be so arranged on handles that it is 
possible to shoot rings from all angles un- 
der the water. When the guns have been 
adjusted and the tank filled, the e.xperi- 
menter is ready to begin his experiments. 

The kinetic energy of these rings is con- 
siderable, as shown by several rather in- 
teresting experiments. If a light watch 
chain be suspended in the path of a ring it 
will be noticeably deflected by the impact 
of the ring striking it, altho the ring itself 
is broken. If a piece of light tissue paper 
is tightly stretched on a frame, and held in 




The Formation of the Vortex Rings. When 
the Diafram Is Moved from D to D", the 
Stream Lines of the Liquid Outside the 
Aperture Will Be Somewhat as Is Indicated 
By the Full Lines. The Liquid Bends Into 
Spirals, Each Particle Moving Towards the 
Place Where the Pressure Is Diminishing, 
and the Ring Formed Continues to Rotate 
Around a Circular Center. 



the path of the rings, the rings will break 
thru the paper, but in turn are broken up 
by the impact. A pretty experiment is to 
similarly stretch a piece of chiffon cloth and 
hold it before the gun. The rings will pass 
thru it without being broken or disturbed 
in their motion. 

If two guns are placed opposite each 
other, and rings be projected simultane- 
ously, it will be observed that if they strike 
each other fairly, both will be broken up. 
If, however, their path is such that they 
would merely have touched on their edges, 
they will bend out of their course and will 
pass each other without injury. This phe- 
nomenon of the mutual repulsion of the 
rings is in accordance with the modern 
idea of the electron ; namely, that they are 
like charges of electricity, which repel each 
other. These vortex rings, of course, are 
not supposed themselves to have any elec- 
tric charge, tho acting like an electron; 
they are simply clever illustrations of what 
an electron is supposed to be. 

If a ring is shot towards the surface of 
the water in the tank, it will be noticed 
that at certain angles, it is reflected from 
the surface and continues in a new path the 
same as the angle of incidence. At other 
angles the ring will not be reflected but 
will jump out of the water with a spurt. 
Besides being reflected it can be shown 
that these vortex rings can be refracted. 
The tank should be half filled with water, 
and a dense solution of Sodium Chlorid 
siphoned into the bottom of the tank, so as 



A word as to the formation of the rings 
by the gun w-ill doubtless be necessary. 
Referring to Fig. 2 it will be noticed that 
when the diafram D is moved from D 




One Way of Making the Liquid "Gun" for 

Shooting Vortex Rings Thru Water as Shown 

In the Illustrations On Opposite Page. 



to make a layer of denser liquid under- 
neath the water. If a swiftly movipg ring 
be shot so as to pass into the salt solution 
at an angle it will be noticed that the ring 
will pursue a slightly downward course, 
curving slightly. 

There are many more experiments in this 
line, which space does not permit us to 
enumerate. We will, however, name a few 
extremely interesting experiments. The 
aperture can be cut in all manner of forms, 
thereby imparting to the ring various vi- 
bratory movements, or two holes can be 
cut near each other, thus projecting two 
rings at the same moment. Rings can also 
be shot into a lighter layer of oil, which is 
poured over the surface of the water, and 
interesting results may be obtained. If it 
is desired to procure actual models of the 
rings, the gun should be filled with melted 
^paraffine, and the ring shot from a layer 
of hot water into a layer of cold water 
beneath. The rings will harden upon com- 
ing into the cold zuatcr, and may thus be 
saved. 







^Smdhe rings 


orifice 


Box' ConfamirTg^^^K^^ 
imohe V i^HH 


i 




^W^^^ '' Agitator 


Fig 3 


t^ 



The Vortex Ring Smol<e "Gun." Every Time 

the Bottom or Diafram of the Box is Struck, 

a Smoke Ring Issues from the Small Opening 

in the Top of the Box. 

to D' the stream lines of the liquid outside 
the aperture will be somewhat as is indi- 
cated by the full lines. After the liquid 
has issued from the aperture it would be 
expected that the liquid would move as the 
broken lines indicate. Instead it bends into 
spirals, each particle moving towards the 
place where the pressure is diminishing, 
and the ring formed continues to rotate 
around a circular center. 

Water is one of the best mediums for 
producing vortex rings, because it is in- 
compressible. It has, however, a great 
viscosity, and internal friction, which pre- 
vents their being permanently formed. Ac- 
cording to the mathematician, in a perfect 
fluid, such as ether is supposed to be, a 
vortex ring could never be created, but if 
once formed could never be destroyed. Thus 
an electron, if it were an ether vortex ring, 
as is surmised, would be indestructible. This 
accords with the theory of matter as ac- 
cepted today. 



TESTING THE QUALITY OF MILK. 

By means of two simple tests it is possi- 
ble to determine with a reasonable degree 
of accuracy the quality of milk. A qualita- 
tive test to show whether the milk contains 
water or not is made in tlie following man- 
ner. Take a perfectly clean steel hatpin 
and imrnerse it point down into the milk. 
If on withdrawing it a film of milk covers 
the same, there is' no free water present. 
On the other hand the presence of water in 
small quantities will prevent the milk ad- 
hering to the pin. 

Should the above test show the presence 
of water the percentage of the same can be 
obtained in the following manner: — Take 
an ounce of plaster of Paris and wet it 
with the milk under test till a smooth paste 
is formed. Allow the paste to dry, de- 
termining the length of time that e'lapses 
before it hardens. The percentage of water 
can then be obtained from the following 
table : 



Time % Water 

20 min. 75 

30 min. . SO 

1 hr. 40 

2 hrs. 25 

3 hrs. 20 

4 hrs. 15 



Time % Water 

5 hrs. 12}4 

6 hrs. 10 

7 hrs. ly, 

8 hrs. S 

9 hrs. 2V2 
10 hrs. 



This test depends on the fact that the 
cream in the milk retards the hardening. 
Contributed by T. W. BENJAMIN. 



714 



ELECTRICAL EXPERIMENTER 



February. 1919 



"Ball Lightning" Experiments! 



By SAMUEL S. VVEISIGER, Jr. 



IN the January, 1916, issue of the Elec- 
TRiCAi, Experimenter you publisht a 
discourse on "Ball Lightning," and gave 
instructions for the experimental pro- 
duction of it. Thru the kindness of 
Mr. Porter, Instructor in Physics at the 




This Is Another "Freak" Discharge. The 
Ball Travelled In a Very Crooked Path to the 
Positive Electrode, and Here Exploded. The 
Force of the Explosion Was So Great that a 
Part of the Spark-Ball Was Thrown to the 
Other Side of the Positive Electrode, from 
Whence It Continued to the Positive 
Electrode. 



Allegheny High School, I have been able 
to make the several photos accompanying 
this letter. Under each photo there is 
given a short description of the circum- 
stances under which each discharge was 
made and the phenomena connected there- 
with. 

In making these photos a 75.000 volt 
Toepler-Holtz static machine was used. 
The distance between the sharp metal 
points was from 5.5 to 6 centimeters. This 
distance must be found by experiment, and 
altho it is absolutely essential to have the 
correct distance between points, it will 
nevertheless differ with the capacity of the 
static machine. 

Much trouble will be encountered if the 
sharp points, used to produce the discharge, 
are not free from grease and highly pol- 
ished. The best way to polish the points 
is to take a little powdered chalk (black- 
board chalk which has been scraped to a 
fine powder with a knife) and put it on 
some kind of cloth and turn the point of 
the electrode, at the same time giving 
considerable pressure to the cloth where 
the point is being turned. 

The best connection for the electrodes 
was found to be obtained by means of two 
brass chains. 

Two large-sized, sharply pointed darning 
needles suitably mounted form admirable 
electrodes. It is practically impossible to 
use blunt needles. 

There will be much trouble in finding 
the correct spacing for the electrodes and 
it will probably require some experimenta- 
tion. In any case the spacing is dependent 
on the power of the static machine. 



as the discharge occurs better when the 
plate is placed in this manner. 

When the plate is under the electrodes 
and the static machine has been started, 
the spark ball should form very quickly. 
After the ball has detached itself from the 
electrode, turn the machine verj' slowly in 
order to expose the plate longer. The rate 
of travel of the spark ball is proportional 
to the speed of the static machine. 

Should the machine be stopt before the 

spark ball reaches the other electrode, the 

plate will only show the path of the ball to 

that point. 

* * * » * 

Knowing that there is considerable in- 
terest in these "Ball Lightning" experiments 
we have republisht below the original di- 
rections for producing ball lightning in the 
laboratory as outlined by the famous 
French scientist — M. Stephane Lcduc. His 
experiment makes possible the production 
of a slowly moving globular spark not 
easily obtainable in any other way, in so 
far as we know. 

To produce this imitation ball lightning 
it is necessary to employ two very fine 
highly polished metallic points, each of 
which is in connection with the positive 
and negative poles, respectively, of a static 
machine of small or medium size. These 




globule as it travels is quite slight, it tak- 
ing from one to four minutes for it to tra- 
verse a path of six centimeters in some 
cases, and before reaching the positive elec- 
trode the globe bursts into two or more 
luminous balls which individually continue 



Some Trouble Was Encountered in Getting 
this Spark-Bali to Form. Evidence of This Is 
Shown By the Plate Being Exposed By a 
Tiny Charge Or Burst of Light On One Side 
of the Negative Electrode. The Uneven 
Course of the Spark- Ball Is Clearly Defined. 

When the plate is put under the elec- 
trodes be sure to get the emulsion side up. 





This Is Probably the Best Photo of the Set, 
the Spark-Bali Being the Largest Obtained. 
You Will Notice the Manner in Which the 
Bail Broke into Two Parts and Each Part 
Proceeded to the Pole. The Effluvium 
Around the Positive Pole Shows Signs of a 
Violent Explosion As Will Be Noted By 
Closely Examining the Tree Formation i^ade 
By the Bursting Spark-Ball. 



their journey to the positive electrode. On 
developing the photographic plate (which, 
of course, should be placed imder a ruby 
light while the foregoing experiment is 
conducted) there will be found a trace on 
it of the exact route followed by the spark 
globule — the point of explosion, the routes 
resulting from the division, and the efflu- 
vium around the positive electrode point. 
Also, if one should stop the experiment be- 
fore the globule's arrival at the positive 
electrode, the photograph will only give the 
route to that point. The fireball takes for 
its course the conductor, which apparently 
short-circuits the static machine. If sul- 
fur or some other powder is thrown on 
the photographic plate while the experi- 
ment is being conducted, and also while the 
ball is moving, its path will be marked by 
a line of aigrettes, looking very much like 
a luminous rosary. 

[The Editors will be glad to hear from 
any of our readers who have made experi- 
ments in this direction. Photographs are 
particularly welcome.— E,X).] 



Scheme for Producing Ball Lightning in the 

Laboratory with Static Machine, Photograph 

Plate and Two Needles. 



two metallic points must rest perpendicu- 
larly, as our illustration indicates, on the 
sensitive face of a gelatin bromid of silver 
photographic plate, which is placed on a 
metallic leaf, such as tinfoil. The two 
metal points are spaced about five to ten 
centimeters apart. When the static ma- 
chine is operated an effluvium is produced 
around the positive point, while at the 
negative point there is formed a luminous 
fireball or globule. 

Now, when this globule has reached a 
sufficient size, it will be seen to detach it- 
self from the metallic point, which then 
ceases to be luminous, and the globule will 
begin to move forward slowly over the sur- 
face of the plate, taking various curved 
paths and eventually it will set off in a di- 
rection toward the positive metal point. 
When it reaches this electrode the effluvium , 
is extinguisht and all luminous phenomena 
ceases. Further, the static machine acts 
as if its two poles were short-circuited, or, 
in other words, united by a conductor. 

The velocity acquired by the luminous 



HORSE-POWER OF WIND MILLS. 

Below is given a table showing the actual 
useful horse-power developed by a windmill 
working under diflferent conditions. 

HORSE-POWER OF WINDMILLS 
Diam. of Velocity of Wind, Miles per hour 
Wheel 8 10 12 16 20 25 30 
in Feet 

Actual useful Horse-Power Developed 
12 'A Vi 'A I 15^ 2 

16 % H Vt i'A 2% 3'A 4 
20 M m 2 3 4 5V4 7 

25 1}4 IJi 3 4J4 6 8 10 

30 2 3 4 5J^ 7 9 12 




This is One of the "Freak" Bali Lightning 
Discharges. The Spark Bail Formed At the 
Negative Electrode and Travelled Straight 
for the Positive Pole, But Did Not Reach It. 
It Disappeared Without Exploding. The 
Machine Was Kept Going and for Some Un- 
known Reason Another Ball Formed and 
Backed Away from the Negative Electrode, 
and Broke Into Two Pieces Before It Reached 
The Positive Electrode. 



February. 1919 



ELECTRICAL EXPERIMENTER 



715 



A Useful Electrical Laboratory 

Switch-board 



By H. DANNER 



A SWITCH-BOARD is a valuable ac- 
cessory to any Experimenter's 
electrical laboratory. The switch- 
board here described is intended 
for use on an alternating current 
circuit of 110 volts, 60 cycles frequency. 
But if the switch-board is to be used on a 
direct current circuit the only changes neces- 
sary are the substitution of D. C. instru- 
ments and the removal of the low voltage 
transformer. 

The marble or slate panel is 3 ft. 10 in. 
long, 2 ft. 6 in. wide and 1 or 1% in. thick. 
It is supported by two angle iron uprights, 
2x2 inches, and 6 ft. 4 in. long, plus four 
inches which is bent back as a foot as illus- 
trated in Fig. 4. To make this bend saw 
off one side of the angle four inches from 
the end and after heating it red bend at 
right angles by putting it in a vise. Use 
a hammer to make a square bend. The 
panel is fastened to the angle irons by six 
a inch bolts as shown in Fig. 1. The 
weight of the marble or slate is supported 
by a piece of angle iron across the bottom 
of the switch-board fastened as shown in 
Fig. 5 (a bolt can be used instead of a 
rivet). The top of the board is braced to 
a wail by means of a flat piece of iron bent 
on one end to permit it being bolted to 
the wall. 

A marble drill should be used in drilling 
the marble, but an ordinary drill will serve 
the purpose. Water will help to drill either 
marble or slate. 

We are now ready for the instruments 
and switches. The voltmeter is preferably 
a Weston model 151, — 150 volt scale 
range. The ammeter is the same model, 
— 150 amperes scale range. Both instru- 




Details of Transformer, Sliding Switch, Switch-Board Support 
and Other Parts Used In Building the Laboratory Switch- 
Board. 



ments are 9}4 inches in diameter. All con- 
nections are made at the back, conforming 
to standard switch-board practise. 

The main line cut-out is of 100 amperes 
capacity and is located be- 
tween the instruments. The 
main line switch, 100 am- 
peres, connects the bus-bars 
to the line. The ammeter is 
connected in series with the 
switch (see Fig. 1). The 
volt-meter is connected to a 
small, double-pole, double- 
throw knife switch, one side 
of which is connected across 
the main bus-bars and the 
other side across the step- 
down transformer outlet. 

The upper set of (copper) 
bus-bars are %" x %" x 24" 
and are spaced two inches 
apart. The bars leading 
from the main line switch 
to the second set of bus- 
bars are of the same size. 
The lower or second set of 
bus-bars are ^" x 3/64 x 
24". 

The bus-bars are fastened 
by No. 8 — 32 copper or 
brass machine screws (%" 
in diameter). All connec- 
tions must be well made. 
The bars are insulated by 
bending them up and over 
the other bars. The switches 
are connected to the bus- 
bars by short pieces of cop- 
per bars. 

The upper row of switches 
consist of 
two 60 
amp. 
D.P.S.T. 
switches 
placed i n 
the center 
and two 
3 amp, 
D.P.S.T. 
s wit ches 

on each side. All the 
switches have fuse clips 
attached of proper ca- 
pacity. 

The four switches in 
the lower row are 15 
amp. D.P.S.T. switches. 

Below this row are 
placed three plug recep- 
tacles, two polarized and 
the other unpolarized, 
located as shown in the 
drawing. A double-pole 
double-throw IS ampere 
switch is placed in the 
middle with a small 
charging rheostat on the 
right. This switch con- 
nects the storage battery 
to the motor-generator 
and to the discharge out- 
let. The plug receptacle 
on the right is connected 
directly to the motor- 
generator and affords a 
source of direct current. 
The one to the left of 
the switch is connected 
to the storage battery 
and is of use in many 



experiments. The plug on the left side is 

connected to the step-down transformer. 

The service to which the individual 

switches are put depends upon the needs 




^^y^^mm^^^rmm^ 




iVfmm*.:5tQBat- „ — „ _, 

Plug. : ; nug. ^"P^'/H *.'*™ - 






A C. Swifc/i board 
100 amp. 



ww^ 



FigL 



Fig. 2 



The Experimenter Desiring an Attractive and Efficient 
Switch-Board Will Find the Design Here Suggested an 
Excellent One. It Is Fitted with A. C. Low Voltage Trans- 
former and D. C. Battery Charging Rheostat, as Well as 
Volt and Ammeter. 



of the experimenter. The two 60-amp. 
switches are intended for the arc, electric 
furnace, or for a 5 K.W. step-up trans- 
former and other apparatus requiring over 
30 amperes. The switch for the arc is 
connected to the stage plug at the bottom 
of the switch-board. A variable resistance 
is connected in series with the stage plug. 

The first switch on the left-hand side, 
second row, connects the primary of the 
step-down transformer to the line. The 
next switch to the right is for a high volt- 
age transformer. Then comes the hand 
wheel or knob of a small field rheostat for 
the motor-generator. The field rheostat is 
mounted behind the board in such a position 
as not to interfere with the o'her apparatus. 
To the right of this comes the motor-gen- 
erator switch, and on the right is the switch 
for the lights. 

The transformer slide at the lower left- 
hand side consists of a ^" square brass rod 
14^" long. Over this rod a Vi," square 
hollow tube, 1 inch long is fitted, with a 
handle and spring contact large enough to 
cover only one contact point at a time. 
The contacts can be made from 5^" round 
brass rod and fastened and connected in 
the same manner as starting box contacts. 
Use your judgment in all of this work. There 
(Continued on page 753) 



7)6 



ELECTRICAL EXPERIMENTER 



February, 1919 



Experiments in Radio -Activity 



By IVAN CRAWFORD 

PART II— Ionization (Continued) 



IN the first installment the construction 
of a super-sensitive electroscope was 
outlined, and the conduction of elec- 
tricity thru gases partially discust. 
Before going further into the mys- 
teries of radio-active phenomena it is fitting 
that further experiments with this electro- 
scope should be given. Another method 




Aluminum leaf -f-r^: 

Ac five subsfonce 



^- 



Home-Made Telescope-Electroscope For Use 
In Studying the Retardation of Alpha Par- 
ticles By Aluminum. 



for the detection of ions will also be given. 

The retardation which an alpha particle 
experiences in its course thru matter, de- 
pends entirely upon the atomic weight of 
the atoms thru which it passes. Bragg and 
Kleeman found that the retardation of the 
alpha particle was approximately propor- 
tional to the square root of the atomic 
weight of the substance. In the case of 
metals, their weight per unit area, required 
to completely overcome the alpha radiation, 
is proportional to the square root of their 
atomic weight. 

It was found that the retardation of the 
alpha particle by complex molecules was an 
additive property. For, consider that a 
molecule is composed of N number of 
atoms of atomic weight W, together with 
N' number of atoms of atomic weight W, 
etc. Then the retardation of the alpha par- 
ticle is N \/\V -!- N, \W 



Sir Ernest Rutherford has determined the 
specific retardation of alpha rays in metals 
both by observation and calculation. A few 
of his results with the commoner metals are 
given below : s is the observed stopping 
power of the atoms in terms of air as 
unity; w is the atomic weight. It will be 
noticed that the quotient s/ 'Vw is approxi- 
mately equal in all cases. 



Metals. 

s 

\|w 

s/ V^X 10" 



Al. 
1.495 
5.2 

287 



Fe. 
2.29 
7.48 



Cu. 
2.46 
7.96 



307 309 



Pb. 
4.27 
14.35 

298 




Fig. 3. — A Very Interesting Experiment Can Be 
Conducted With a Geissler Tube and Spark Gap, 
Excited By a Spark Coil, In Connection With Some 
Radium Bromid. The Radium Will Dim the Tube, 
the Spark In the Gap Becoming Heavier. 



By a series of simple experiments the 
reader may determine the retardation of 
alpha particles by thin sheets of the com- 
moner metals. On a grounded metal disc a 
quantity of radium bromid is placed. See 

Fig. 1. Thin sheets of 

aluminum, brass, copper, 
iron and lead should then 
be interposed between this 
active material and the 
electroscope. The discharg- 
ing current should then be 
measured as outlined in 
the previous paper. The 
sheets of the various 
metals should be of the 
same thickness to allow 
comparison. It will be no- 
ticed that the experimental 
results will compare very 
favorably with the calcu- 
lated values. 

A very interesting ex- 
periment is to interpose 
successively various thick- 
nesses of aluminum be- 
tween the radium bromid 
and the electroscope. With 
the electroscope empty the 
gold leaf past over five 
divisions on the scale in 
412 seconds. The time 
with uncovered radium 
bromid was 15 seconds. 
Upon placing a sheet of 
extremely thin aluminum 
ionizing agent the electroscope discharged 
in 25 sec, showing that a portion of the 
alpha radiation was stopt by the 
aluminum leaf. When a sheet of 
aluminum foil about .001 of an inch 
thick was interposed, the electroscope 
was discharged in 137 sec. A sheet 
of aluminum .01 of an inch thick 
ruts off the entire radiation, and the 
ionization caused by beta particles, 
which easily penetrate this nb?tacle, 
is very small, discharging the elertro- 
srope in about 380 sec. A sheet of 
lead cuts off the entire radiation, the 
electroscope discharging the same as 
when empty. 

To determine the retardation of 
alpha particles by aluminum the fol- 
lowing experiment may be performed. 
The radium bromid is covered by suc- 
cessive layers of aluminum leaf and 
the discharging current measured in 
each instance. For radium the ioniza- 
tion falls off in geometrical progres- 
sion as the thickness of the aluminum 
is increased. Thus, as Makower has 
shown, where L is the intensity of 
the active substances uncovered, 
then I is the intensity when a 



thickness of aluminum, t, is interposed. 
I r= loe-'^' 
Where e is the base of the Naperian 
logarithms and X is an absorption constant 
which has a different value for each sub- 
stance. It is proportional to s in the pre- 
ceeding table. This law holds true for 
homogeneous radiations, but when using 
ordinary radium bromid as an ionizer, four 
sets of rays are given off, each having a 
different penetrating power. Until the 
thickness of the aluminum is great enough 
to cut off one set of rays the law given 
above will hold true. The author has 
found that about 6 thicknesses of aluminum 
are sufficient to cut off the first set of ra- 
diations. In the accompanying graph Fig. 2, 
the full line indicates the successive stop- 
ping powers up to 6 thicknesses of alum- 
inum leaf for radium as determined by 
Rutherford. These results were obtained 
by the author and experiments by the 




Graphic Chart Showing the Effect of Different Thicknesses of 
Aluminum In the Retardation of Alpha Particles. 



leaf over the 



reader should be proportional to these. 

That the radiations given off by radio- 
active materials ionize the air into positively 
and negatively charged carriers can be 
readily proven by the following experi- 
ment : Connect a spark gap with an induc- 
tion coil and with a vacuum tube as indi- 
cated in Fig. 3. A large Geissler tube will 
give excellent results, the larger the better. 
The spark gap should be capable of fine and 
delicate adjustment. The coil must not 
give too strong a discharge, but the dis- 
charge must be very steady. Arrange mat- 
ters so that the coil gives a steady discharge 
at the spark gap and then draw the elec- 
trodes apart until the discharge just passes 
thru the vacuum tube, only an occasional 
spark crossing the gap. A small quantity 
of radium bromid is then brought into the 
vicinity of the spark gap. When this is 
done the Geissler tube will be partially 
dimmed and the discharge will pass by way 
of the spark gap. The greater the amount 
of radium bromid used the more the tube 
will be dimmed. This is caused by the ions 
formed by the radiations from the active 
radium bromid. If care is taken that the 
conditions named above are secured the ex- 
periment will ^Iwnvs be successful. 
(To be continued) 



February, 1919 



ELECTRICAL EXPERIMENTER 



717 



Experimental Mechanics 

By SAMUEL D. COHEN 



ANOTHER valuable feature that the 
lathe possesses is the cutting of 
tapers. Standard tapers are rated 
- at the amount with which the diam- 
eter changes in a foot's length. We 
will take as an instance the standard Brown 
and Sharp taper, which is one-half inch per 
foot, and how it is turned in the lathe. 




Measuring Off the Required Distance Be- 
tween the "Live" and Tail-Stock Centers, 
Preparatory to Turning a Taper in the Lathe. 

First, it can be turned by the use of a 
taper attachment on the saddle of the ma- 
chine, or else bj' offsetting the tail-stock 
from its regular central position to give the 
required rate of change in the diameter. In 
all taper attachments the settings are grad- 
uated to read direct. Thus it is easy to set 
the tool for cutting the prescribed taper. 
The second method of offsetting the tail- 
stock is not as simple as the first. If the 
distance of the center points enter the work, 
or the mandrel is ignored, the mandrel 
length can be considered as the distance be- 
tween the central points. In order to de- 
termine at what length the centers shall be 
offset for a given taper, a simple arithmeti- 
cal calculation will be required. This is 
done by multiplying the length of the work 
or mandrel in feet by one-half the required 
taper in inches. To turn a Brown and 
Sharp taper on a piece of work nine inches 
long, the problem would work out in the 
following manner. This particular calcula- 
tion refers to the one-half inch taper per 
foot specified in the opening paragraph of 
this lesson : 

^2 9 3 

— X — = 0.1875 = — inch. 

2 12 16 

The value of 3/16 inch would be the re- 
quired amount necessan,' to offset the cen- 
ter of the tail-stock. The off-centering is 
accomplisht by unscrewing the set screw 
on the base of the tail-stock and shifting 
it towards the cutting tool 3/16 inches away 
from its original center-line position. Fig. 
1 illustrates the simplicity of accurately 
figuring the exact position of the respective 
centers by the use of a steel scale or rule. 

It will be noticed that in the above Uus- 
trative problem that both the length and 
amount of taper are given. However, at 
times it happens that the amount of taper 
is not given. Let us suppose that a piece 
eight inches in length is to be turned on one 




LESSON X 

end. The taper portion should be four 
inches in length. The difference in diam- 
eters of this four inch section is to be one- 
half inch. The problem is, how much must 
the tail-stock be offset? If the taper is Yi 
in 4 inches, it would be l;4 inches in a foot 
or three times as great, and the tail-stock 
would be moved over one-half of 1J4 inches 
or J4 inch. This calculation holds good 
were the piece a foot long, but as it is 
8 inches, or J^ of a foot, the tail-stock 
should be moved over % x ^, or '/z inch. 
Should the piece be twenty inches long, the 
tail-stock would be moved IJ^ x ^4, or 1% 
inches. 

The above problem was assumed for 
simple calculation, the lathe centers merely 
touching the ends of the working piece, 
thus making the length of the piece the 
same as the distance between the centers. 
In actual practise the depth of the centers 
in the work must be considered. The cal- 
culation should be as accurate 'as possible 
to avoid continually changing the tail- 
stock in order to get a reasonably good 
taper fit. The necessity of considering the 
exact distance between centers depends 
somewhat upon its length. If the piece is 
very long the actual taper will differ consid- 
erably from the calculated taper. If each 
center enters the piece H inch they would 
enter a total of Vz inch. The length of the 
piece should thus be reduced by yi inch in 
the calculation. While turning the taper, 
the calipers should be used frequently so 
that it may quickly be determined whether 



--[ 


■; 




' 


][ 


^H-M 


^^^ 


n 


i 1 







^ ^. ^- = 




f/ff 4 


A 

r 

tt. 



Diagram Showing Plainly How a Piece of 
Stocl< Is Placed Between Off-Set Lathe Cen- 
ters When It Is To Be Turned On a Taper. 



Eccentric Discs For Steam Engines and the 
Like Are Bothersome Jobs To Turn. This 
Diagram Shows How An Eccentric Is Readily 
Centered On An Arbor Having Off-Set 
Centers. 

or not the tail-stock is correctly placed for 
the job in hand. 

In order to test the accuracy of the taper 
as it is turned it should be prest lightly 
into a standard tapered hole and worked 
back and forth sufficiently to mark the 
places where bearings points occur. If the 
work has been lightly covered with some 
marking pigment (chalk), the bearing 
points will be more distinct. However care 
must be taken that the coating is not too 
heavy, as it will be liable to deceive the 
amateur. Adjust the taper setting until a 
correct fit is obtained. 

Another very good method of testing the 
exactness of the taper is to obtain another 
taper mandrel or form of standard size, 
having the same taper pitch, and placing its 
surface against the one cut, as shown in 
Fig. 2, where either A or B can be the 
standard. Then set a pair of calipers on 
one side, and run over the entire surface 
with the same setting of the calipers. If no 
indication is shown of surface irregularity 
the taper is said to be true ; if high or low 
marks are present, the taper is not true and 
a readjustment of the tail-stock setting is 
necessary to correct it. 

In turning down a taper the centers must 
be employed. This work must be turned 
down with the aid of the face plate and dog 
shown in Fig. 3, which illustrates the posi- 



tion of offset work for taper cutting. A 
lathe chuck cannot be used for this class 
of work, as the piece to be turned down is 
kept rigidly in place in a central position, 
thus preventing its position from being 
offset. The chuck is used only when a 
taper attachment is employed. It should 




One Method of Testing the Accuracy of a 

Tapered Piece By Placing It Alongside a 

Standard Taper, and Running the Calipers 

Over Them, 

never be used otherwise. At times in cut- 
ting a very short taper or conical point and 
when a compound rest is at hand the com- 
pound rest is turned to an angle equal to 
the angle of -the taper to be cut. How- 
ever it is advisable to adhere to the simple 
method of cutting a taper and as soon as 
the novice feels quite safe with this method 
he will then be at liberty to try those more 
difficult. 

The experimenter who is mostly familiar 
with the use of the lathe for turning con- 
centric objects will now see that the lathe 
is just as useful in turning objects of ec- 
centric shape. The most common of such 
objects is the eccentric which operates the 
valves of a steam engine. If the work has 
a hole thru it, as in the above example, the 
hole is first finished to the required dimen- 
sions and then a mandrel is used for carry- 
ing the work on the lathe centers. While 
the mandrel has been built on one set of 
centers exactly true with its axis, for con- 
centric turning, it has a second set of cen- 
ters which offset the amount required for 
the eccentricity specified. In the case of ec- 
centrics made solid with the shaft, there 
are two sets of centers, one for turning the 
shaft — and the other for stabilizing the op- 
posite end of the shaft. Fig. 4 shows how 
such an eccentric is arranged in the lathe 
for proper turning. Note the position of 
the central axis of the object with respect 
to the live and dead centers of the lathe. At 
certain times the specified eccentricity is too 
extreme to allow both pairs of centers 
coming within the limits of the diameter of 
the shaft. Special ends may be cast, forged 
(or clamped) on the ends of the work, and 
can afterward be machined off. In crank- 
shaft turning, special attachments should 
be provided for the ends of the shaft, or 
special chucks for eccentric turning may 
be made to hold the work. 

The turning of crank pins on shafts is 
{Continued on page 749) 




Blocking Up a Crank Shaft By Pieces 5-5, 

and Clamps 3-3, So As To Make It Rigid 

While the Bearing 1 Is Being Machined In. 

the Lathe. 



718 



ELECTRICAL EXPERIMENTER 



February, 1919 



ARSENIC: History. 

THE ores of Arsenic, in the form of 
its two sulfids, Realgar and Orpi- 
inent, were known to the Alchem- 
ists. Geber was famihar with the 
oxid, and Mangus refers to the 
metal ; but Brandt, in 1773, first showed 
that white arsenic was obtained by burn- 
ing the metal. 



Porchment 
membrane 




F/g. /56 



Dialyzer Used For Separation of Arsenic 

Prior to Applying the "Marsh" or Other Test 

For the Element. 



Occurrence. 

This metal is quite widely distributed in 
nature, while in the free state it is occa- 
sionally found in distinct crystals. It is 
more abundantly distributed in the com- 
bined stated, as Arseiwlile [As^Os], or the 
sulfids, as Orpiment [As-Sj], and Realgar 
[As;S:], or in the form of the metallic 
arsenids. Arsenical iron [FeAsj], and Ar- 
senopyrit [FeAsS]. It is also found in re- 
ducing ores of Nickel, Cobalt, etc.. being 
obtained as a by-product of Cobalt Glance 
[CoAsS] and Xickel Glance [NiAsSl. 

Preparation. 

Metallic arsenic is prepared by subliming 
the native mineral or by reducing arsenous 
oxid with charcoal : 

As:0, -f 3C = 2As 4- 3C0. 
Probably the largest quantity is prepared 
by subliming arsenical pyrits : 

2FcAsS - 2As + 2FeS. 
In the first process above mentioned, the 
arsenical pyrits are oxidized by roasting, 
that is, heating with access of air. This 
gives the oxids of the three elements, 
FesOi, AsjOi, SOi. The first remains be- 
hind in the retort, SOi escapes as a gas, and 
AsjOi sublimes. It may be purified by re- 
subliming. The metallic arsenic is obtained 
by reducing the oxid with charcoal. 
As=0. -I- 3C = 3CO + 2As. 
2As:0. -f 3C = 3C0. -I- 4As. 
Some Arsenic can be obtained by exclud- 
ing air and heating FeAsS. 

FeAsS = FeS -|- As. 

Properties. 

Arsenic appears usually in the form of a 
steel-gray, brittle, crystalline mass, of me- 
tallic luster. 

It is a good conductor of electricity. 

It is easily volatile, then possessing a 
garlic odor. 

It hardens lead when alloyed with it; 
hence its use in shot manufacture. 

When roasted in air, it forms As:Oa. 
When air is past over it in a hot combustion 
tube, it burns with a blue flame. 

It has great attraction for chlorin, burn- 
ing in it like antimonv, to form the chlorid, 
AsCU. 



Experimental Chemistry 

By ALBERT W. WILSDON 

Thirty-third Lesson 

Like its salts it is poisonous when taken 
into the stomach. 

At a temperature higher than 180°C., it 
unites directly with most elements. 

It unites with metals to form arsenids, 
analogous with the sulfids. 

Oxids. 

Two oxids are known Arsenious Oxid 
(As.Oa) [usually written AsiOa and called 
arsenic trioxid, Arsenious Acid, Arsenic, 
White Arsenic, etc.], and Arsenic Oxid 
[AsiOs]. The former only is important, be- 
ing the most important commercial com- 
pound of the element. From this other 
compounds of the metal are formed. It is 
a white substance, sometimes amorphous 
and sometimes crystalline, which resembles 
flour when pulverized. It dissolves ver>- 
slightly in cold water, upon which its par- 
ticles seem to have a repellent action, but 
on boiling for a long time more dissolves. 
The best solvents are Hydrochloric Acid 
and Alkalies. With Hydrochloric acid it 
forms : 

As=0, -f 6HC1 = 2AsCL, -|- 3H,0. 

Salts. 

There are two classes of salts, the — ate 
and the — ite, of which Sodium Arseniat 
[NajASO.] and Sodium Arsenit [NaaAsOa] 
are examples. In the former, the valence 
of Arsenic is 5, in the latter 3. The — ite 
salts are more frequently met with. The 



Bo/f/e n/ifh 
boftom cutouf 




Successive Stages In Preparing a "Marsh 
Tube." 

Sulfid [AsjSa] is a permanent and brilliant 
yellow pigment made by passing Hydrogen 
sulfid gas into a solution of an • — ite salt. 
Scheele's Green [HCuAsOs] and Schwein- 
furt or Emerald Green [CuCAsOal^.CuAsOj 
CiHaOJ both go under the name of "Paris 
Green," and are much used as pigments, 
especially for green window blinds, ship- 
ping tags, silks, etc. ; also extensively cm- 
ployed by farmers to exterminate the po- 
tato beetle. Wall papers at one time almost 
always contained Arsenic, but now — owing 
to better substitutes and legislative prohibi- 
tion — they rarely contain it. Scheele's 
Green is made by adding a solution of 
copper salt, as CuCU, to an arsenious salt 
solution, as HNa^AsOa. If these are nearly 
neutral, a precipitat of HCuAsOa is ob- 
tained, but if strongly acidified with Hy- 
drochloric acid or alkalized with NH.OH, 
no precepitat falls, which is the same as 
saying that Scheele's Green is soluble in 
either of the reagents. Fowler's Solution 
— used in medicine — is Potassium Arsenit. 



Tests. 

There are Four important tests, Marsh's, 
Reinsch's, the Carbon, and the Hydrogen 
Sulfid. Besides these there are The Modi- 
fied Gutccit Test, Bettendorff's, etc. 

MARSH'S TEST.— This is the most 
delicate and interesting, and consists in 
first forming Arsin [AsHa], then decom- 
posing it and subliming the arsenic. Any' 
soluble arsenical compound in presence of 
nascent hydrogen forms Arsin, which is 
readily decomposed by heat, when the ar- 
senic sublimes. By tliis process a quantity 
far too small for the most delicate balance, 
can be detected,— in fact a mere trace of 
the element. 

Explanation. — Suppose the compound to 
have the composition AsX.,, in which X is 
any nonmetallic monad. Hydrochloric acid 
gives this reaction : 

AsXa + 3HC1 = AsCla -f- 3HX. 
Nascent Hydrogen decomposes AsCla 
and combines with both elements. 
AsGl, -f 6H = AsHa + 3HC1 
The Arsin passes out and is burned to- 
gether with the excess of hydrogen. 

2AsHa -f 60 = ASjOa -f 3H:0. 

A Bunsen flame decomposes the Arsin. 
AsHa= AS-I-3H. 
when the metal sublimes in the capillary 
tube. The question arises whether any 
other element than arsenic would act in a 
similar way. Antimony acts almost ex- 
actly like it, forming gaseous and com- 
bustible Stibin [SbHa], which likewise de- 
composes and sublimes as a metallic mir- 
ror. Several tests serve to distinguish the 
sublimed Arsenic from Antimony, the best 
being the solubility of Arsenic in Sodium 
Hypochlorit [NaClO] and the insolubility 
of Antimony. The quantity of Arsenic can 
be determined by comparing the depth of 
shading of the deposit with that of tubes 
containing a known quantity. 

REINSCH'S TEST.— This consists of 
depositing Arsenic on copper, then oxidiz- 
ing the Arsenic and subliming the AsaOa 
formed. 

The compounds of Arsenic will first 
change to AsCla by Hydrochloric acid. The 
copper in the heated acid will withdraw the 
arsenic and deposit it, leaving copper 
chlorid in solution. Heat will vaporize the 
arsenic, which at the same time will com- 
bine with the oxygen in the tube to form 
As-Oa, and this in turn will sublime as a 
white solid on the cold sides of the tube. 
Identification is then made by examination 
under a microscope, when a portion of it 

{Continued on page 750) 




Apparatus Utilized For Performing Marsh's 
Test For Arsenic. 



February. 1919 



ELECTRICAL EXPERIMENTER 



719 




This department will award the following monthly prizes: First Prize, $3.00; Second Prize, $2.00; Third Prize, $100 
The purpose of this department is to stimulate experimenters towards accomplishing new things with old apparatus or old material 
and for the most useful, practical and original idea submitted to the Editors of this department, a monthly series of prizes will be awarded' 
For the best idea submitted a prize of $3.00 is awarded; for the second best idea a $2.00 prize, and for the third best prize of $1 00 The 
article need not be very elaborate, and rough sketches are sufficient. We will make the mechanical drawings. Use only one side of sheet 
Make sketches on separate sheets. . 



FIRST PRIZE, $3.00 



AN ELECTRIC FLAG FOR THE 
LAPEL. 

The materials necessary for this are : 
3 feet of electric cable, a flashlight bulb, 
a flashlight batterj', a small U. S. (or 



■j1 



LI 



B. 



hremri; j] 





Fig. 2 f/g.S 




Fig J Fig 4 Fig, 6 



Fig- 7 „ 



An Electric Lapel Flag Which Anyone Can 

Make from a Piece of Twin Cord, a Pocket 

Flashlight, and a Small Paper Flag. 

service flag) paper flag and some card- 
board. Fix the cable as shown in Fig. 
1, and then bend both wires on each end, as 
shown in Figs. 2 and 3. Make a cardboard 
box an inch larger each way than the flag 
and f^-inch thick. On the front cut out 
an oblong opening ^-inch smaller all 
around than the flag. Paste the flag over this. 
Contributed by FRANCIS <J . SLAGT. 



INTENSIFYING THE SHOCK 
FROM MAGNETOS. 

Most people are aware that the "mag" out 
of an old-fashioned telephone makes a fine 
■ "shocker." My "rig" will increase its shock- 
ing capacity tremendously, as all who try it 
will be fain to believe. 
_ Cut a piece of thin brass of suitable 
size to rest against the driving wheel when 
it (the brass) is secured to the base. No 




Tfiis mre IseK^sfD oMerco/rn ofmc^. u 



The Addition of a Simple Spring Greatly In- 
tensifies the Strength of Shock Obtainable 
from a Magneto. 



dimensions are given a^'the mageto-ringers 
varv in size. ,' 

Contributed by L. G. S. TROREY. 



SECOND PRIZE, S2.00 



THIS MICROPHONE MAKES 
AUDIBLE THE FLY'S FOOT-STEP. 

This microphone, when properly con- 
structed, is capable of making audible the 
footfall of a fly, the drawing of a thread 
across the instrument, the slightest touch 
on the table on which it is placed, the blow- 
ing of one's breath upon it, etc., etc. To 
construct this instrument first take a cigar 
box and remove the lid. Next hunt up a dis- 
carded alarm clock and remove the hair- 
spring. Secure a piece of wood, 4"xlJ/2" 
upon which to fasten the uprights, and a 
piece of copper sheeting or any other suit- 
able metal for the uprights. Connect these 
as in the diagram. From an old flashlight 
battery obtain the necessary carbon. Fasten 
the hair spring onto one upright, and the 
carbon to the other, first hollowing out a 



Carbon 



ita/'-50''ing 




<19 



-lllil^ - 



Receiver Ion 
resistance so/imi 



A Supersensitive Microphone Made from a 

Cigar Box, a Piece of Carbon, and a Low 

Resistance Telephone Receiver. 

place in the end of the carbon to receive the 
end of the hair spring; about 3/16 to Yi inch 
deep is sufficient. The right pressure of the 
spring upon the carbon must be obtained be- 
fore the instrument will transmit properly. 
The spring must touch the carbon at all 
times. Connect up a battery (dry cell) and 
a low resistance (5 ohm) receiver, 
ascertain the correct pressure, and 
the microphone is complete. 

Test it by gently touching the 
cigar box ; a whirring noise will be 
heard if everything is all right. 
Blow gently upon it; it again 
whirrs. If placed in the open it 
will indicate when the wind is 
blowing, and by the amount of 
noise, the velocity can be judged. 
Under certain conditions, it will 
transmit speech, whistling, and so 
forth. 



Contributed by 

FRED C. DAVIS. 



THIRD PRIZE, $1.00 



CONTACT POINT FROM 
UPHOLSTERY NAIL. 

An ordinary upholstery nail is flattened 
with a hammer and a hole punched thru 
it with a set punch, as shown in sketch. "The 
hole serves to thread and hold the wires. 
This is a cheap and practical contact point 

Contributed by BERT O'LEARY. 




At Left — Contact Point Made from Up- 
holstery Nail. At Right— The Platinum Ring 
That Becomes Red Hot in the Presence of 
Alcohol. 

WHAT MAKES THE PLATINUM 
RING HOT? 

If a platinum ring (or even a piece of 
platinum wire) is warmed gently for a few 
moments and then suspended in a glass, 
having a small amount of alcohol in the 
bottom, the platinum will become red hot. 
The glass had best be covered with a piece 
of pasteboard having a hole in the center. 
The phenomena may be explained by the 
fact that platinum has the peculiar property 
of causing certain gases to condense on 
its surface. The condensation of alcohol 
fumes is so rapid as to cause the platinum 
to become incandescent. 

Contributed by S. S. GARRETT. 



SEWING MACHINE MAGNET 
WINDER. 

Herewith is illustrated a wire-winding 
machine which is easily constructed. Most 
all wire winding machines are turned by 
hand, but by using this scheme you can both 
wind faster and easier. The pulley of the 
machine is brought against the belt of the 
sewing machine and the same is caused to 
turn due to friction. 

Contributed by E. T. JONES. 



,6eit of ieif^ing machine Adjuzlable for 

Coil to be Nound o/Tsize coils 

i 




^ 



Old Sewing Machine Makes a Capital 
Magnet Winder. 



720 



ELECTRICAL EXPERIMENTER 



February, 1919 




EDITED BY S. CERNSBACK 



A HOME-MADE GAS TORCH. 
As I needed a gas torch I set about to 
make one. I first procured two pipes, one 




Chech voire 



Asr compressor 



To Make This Gas Blow Torch You Will 
Require a Bicycle or Other Small Pump, a 1 
to 5 Gallon Can, and Two Lengths of Rubber 
Tubing to Lead the Gas and Comprest Air 
to the Torch Handle. 

3/16 and one Ji inch in diameter and about 
8 inches long. I then drilled a hole in the 
quarter inch pipe and bent it as shown in 
drawing and set the other pipe into it. The 
handle is of oak with the edges rounded and 
two holes drilled thru it to fit each pipe. 
The air and gas supply come thru rubber 
hoses. A veo' good air compressor is 
made out of a bicycle pump and a one 



gallon can ; the gas may be taken from the 
gas service pipes or from a carbid gen- 
erator. 
Contributed by HERBERT PEHRSON. 

HINTS ON DRILLING GLASS. 

Drilling glass is a difficult proposition 
and very few amateurs possess tools suit- 
able for this purpose. The following ap- 
paratus will drill holes, varying in size 
from the smallest up to an inch or more. 

First procure a brass tube the outside 
diameter of which measures the same size 
as the desired hole. Revolve this on the 
surface of the glass, either by hand or bet- 
ter by means of a small hand drill. The 
drilling must be started by allowing the 
lower end of the tube to be guided by a 
wooden block, with a hole cut in it the size 
of the tube. After the tube has past thru 
the glazing this guide can be removed. An 
excellent abrasive for this drill is emery 
dust and turpentine. It is an excellent idea 
to drill from both sides, since this results 
in a clean, smooth hole. 

Contributed by PAUL G. EDWARDS. 

COINS FOR WEIGHTS. 

In an emergency, ordinary coins can be 
used as weights. The weights given in the 
following table are near enough for all 
the usual purposes. 

Dime weighs 40 grains 

Cent weighs SO grains 

Nickel weighs 80 grains 

One-quarter Dollar weighs 100 grains 
One-half Dollar weighs.. 200 grains 

One Dollar weighs 400 grains 

By simple addition and subtraction a great 
many different weights can be made with 
these coins. For instance, to obtain a 
weight of 20 grains, place a nickel on one 
side of the scales and a quarter on the 



other, and then add enough of the chemical 
to balance it. 
Contributed by HUGO J. ENGEL. 



A RELIABLE HYDROGEN SULFID 
GENERATOR. 

Herewith is a plan and description of a 
simple and cheap hydrogen sulfid generator. 

This hydrogen sulfid generator has given 
very satisfactory service to the author. It 
can also be used for generating hydrogen, 
carbon dioxid, etc. 

The necessary parts are : 

1. Student lamp chimney. 

2. Glass or porcelain jar (a large fruit 

jar will do). 

3. Glass stop cock. 

4. Rubber stoppers, three hole and one 

hole. 

5. Iron sulfid (FeS). 

6. Hydrochloric acid (HCl). 
Contributed by JOHN R. BUXTON. 



One hole stopper. 



Sloss jor 
tlCtdllute--' 




-■'Stop-coc/! 



Jtudenf lamp 
' chimney 



- •> ,f>s 



_J hole rubber 
CorAerpieeeof 
/eac/ 



A Simple Yet Reliable Hydrogen Sulfid Gen- 
erator Made From a Few Odd Pieces of 
Apparatus to Be Found About the Laboratory. 



THE PREPARATION AND USE OF 
BLUE-PRINT PAPER. 

The following describes the manufacture 
of blue-print paper in terms that can be 
easily understood by any one. No difficulty 
should be experienced in either the making 
or the use of the paper. 

In order that the best results be ob- 
tained it is necessary that good material be 
used. All vessels in which the solution 
is made should be kept clean and when not 
in use should have water in them as far 
as possible. Do not use soap when washing 
the trays, as the least trace will do harm to 
the solution. 

Where ordinary work is to be done, any 
kind of well sized paper will answer, if 
toueh enough to be washed. DiflEerent 
grades of unsensitized papers can be bought 
at engineers and photo supply houses. 

The following formula is for a good so- 
lution that will give excellent results to the 
amateur; this solution is made up of two 
salts, dissolved in water and applied to the 
surface of the paper : 

Solution No. 1. 
Ferrocyanid of potassium. ... 1 oz. 

Pure or distilled water 6 oz. 

Solution No. 2. 

Ammoniocitrat of iron 1 oz. 

Pure or distilled water 6 oz. 

When solutions are to be used mix equal 

parts of 1 and 2 and filter thru cotton or 

filter paper. This solution we will call 

No. 3. 

The solutions should be applied to the 



paper in a dark and dry room with a verj' 
subdued light — just enough to barelj' see by. 

Small sheets of the paper may be best 
covered by floating upon the surface of 
No. 3. This is done by taking a sheet by 
two diagonal corners and laying it gently 
on the surface of the solution. This method 
does away with the possibility of air bub- 
bles forming. 

One minute or less will be sufficient for 
sensitizing. Remove the paper by drawing 
over the edge of the tray to remove any 
surplus liquid. Take care to prevent any 
solution from getting on the back of the 
paper. 

Large pieces are best sensitized by tack- 
ing down upon a smooth table with thumb 
tacks and painting the solution on with a 
wide camel's hair brush. Take care to get 
it on quickly and evenly. Dry the paper by 
hanging up by its corners to a wire so that 
it will swing free. Before sensitizing a 
batch of paper it would be best to make a 
trial sheet and print it. The solution may 
not be mixed properly or the paper may be 
too absorbent, in which case the solution 
will go into the paper and will not come out 
when washing, thus causing the print to 
fade in a short time. 

After the paper has dried hard and with- 
out the slightest trace of dampness it should 
be rolled up and put into an airtight (tin 
or cardboard) tube and kept in a dark and 
dry place. 

Printing is the exposing of the sensi- 
tized paper to the acf'on of a powerful light 



with the copy to be printed placed over the 
paper. The direct rays of the sun are best 
for printing, but the electric arc is nearly as 
quick and has the advantage of being al- 
ways constant — regardless of weather. 

The drawing, tracing or negative is 
placed in the frame next to the glass with 
the paper under it, having its sensitive side 
up. Exposure will vary from two to ten 
minutes, according to the light and tracing. 
The correct time is only found by experi- 
ence. 

After the paper is sufficiently exposed, it 
is taken from the frame and immersed in 
a bath of clean running water. A print 
should be washed for not less than fifteen 
minutes or it will fade when placed in the 
light. 

Excellent prints may be made in the fol- 
lowing manner: Slightly expose the print 
so that when it is washed the white lines 
are not clear but appear bluish. Take the 
print out of the bath and lay it on a table 
and sponge it with a solution made up of 
one pound of bichromat of potash and two 
gallons of water. The lines will come out 
pure white and the background an intense 
blue. Wash print thoroly and dry. 

White lines may be added to blue prints 
by the use of a solution made of soda and 
water to which a small quantity of prepared 
chalk has been added to thicken it. This so- 
lution may be applied with a ruling pen. 
Engineers generally use a white, red or 
yellow pencil for making corrections. 

Contributed by RUSSEL MERRELL. 



February, 1919 



ELECTRICAL EXPERIMENTER 



721 




Telephone Amplifier- 

(No. 1,280,556; issued to Louis 
Scher.) 
A telephone amplifier providing 
a loud-speaking portable telephonic 




apparatus enabling persons with im- 
paired hearing to satisfactorily use 
the ordinary telephone. The usual 
Bell telephone receiver is placed 
on top of the cabinet in which there 
is an opening communicating with a 
dictaphone transmitter. The trans- 
mitter in turn is connected from a 
rheostat and battery as well as 
switch-hook to a low resistance, loud- 
speaking telephone receiver. 

Signaling Apparatus. 

(No. 1,280,705 ; issued to Fulton 
Gardner.) 
An ingenious signaling apparatus 
comprising an electromagnet in a 
receptacle, together with a coherer 
form of armature, the whole arrange- 
ment operating an alarm bell when 
actuated by voice or other sound 
waves. It is intended for bank vault 
protection and the like. The sound 
waves impinge on the microphone 
which is connected with a battery 




and primary of an induction coil. 
The secondary of this induction cotl 
connects with the electromagnet of 
the relay shown in cross-section. 
This electromagnet acts on an iron 
filing armature, causing the filings 
to cohere, and thereby closing the 
bell signal circuit. A condenser is 
shunted across the bell in order to 
provide a more steady current by 
virtue of its charging and discharg- 
ing action. 



Telegraph Transmitter. 

(No. 1.280,566; issued to John J. 
Sherry and John L. DuFrane.) 
A clever mechanical arrangement 
comprising an automatic machine for 
sending out dots and dashes, either 
on a telegraph or radio circuit, by 
means of which one unskilled in the 
art or unfamiliar with the code may 
send a distress message from a ship, 
etc. The device should . prove a 
6ne auxiliary in all ship radio rooms, 
especially in case of fire, etc., as the 
transmitter could keep the radio ap- 




paratus sending out distress calls 
with location and name of ship, even 
tho the operator had to abanaon the 
wireless room. There is provided a 
circular disk with a groove around 
its perifery, and in this groove there 
can be placed various telegraph 
character slugs and spaces. Thus 
the notched slugs corresponding to 
dots and dashes actuate a pawl mem- 
ber, opening and closing electric 
contacts in the manner apparent. 



Non-Recoil Gun. 

(No. 1,280,576; issued to Andrew J. 
Stone and William Shuker.) 
A novel form of non-recoil gun 
intended for use on aircraft, etc., 
in which the recoil of the shell 
charge is minimized by the discharge 
from the gun of an 'inertia mass," 
in a direction opposite to that in 
which the main projectile is shot. 
The inertia mass in this design is a 
small affair, and the reduction in its 
weight, as in other guns of this 




type, is made up for by the in- 
creased friction encountered by the 
mass, owing to the reduced bore of 
the barrel thru which it is simul- 
taneously discharged with the main 
projectile. The inertia shell may 
be a copper disc or cup. The charge 
of explosive is fired by an electrical 
primer as shown, or by other means. 
The design of the gun is so com- 

guted that the inertia due to the 
eavy weight of the effective pro- 
jectile plus the light frictional re- 
sistance of the projectile in the gun 
barrel, shall equal the inertia effects 
of the lighter weight of the disc 
plus the heavier frictional resistance 
of the said disc in the barrel. 



Thermic Radio Detector and Tele- 
phone. 

(No. 1,281,742; issued to Hendrik 
Zwaardemaker.) 
This novel invention comprises 
a new form of thermic telephone 
and detector combined, and is suit- 
able for use in wireless telegraphy 
and telephony. Prof. Zwaardemaker 
states that he has observed that the 




Wm^f 



sensitiveness of the thermic tele- 
phone, serving simultaneously as de- 
tector, can be considerably increased 
when it works with polarization, 
I. e., by pre-heating it by means of 
a constant current such as that sup- 
plied by a battery as shown in the 
diagram. The battery may have a 
tension of two to four volts, and 
for increasing the sound, a variable 
and tunable condenser is connected 
in parallel to the thermic telephone 
element. 



Dancing Toy. 

(No. 1,280,307 ; issued to Harry 
_ Rust.) 
This is an interesting electric toy 
and comprises a jointed doll or other 
figure suspended at the top in the 
manner shown. Underneath the fig- 




•^ 



^^d& 



ure there is a spring platform, one 
end of which is provided with an 
electric contact, and also an electro- 
magnet to attract it. The action is 
as follows: When the switch is 
closed, the magnet attracts one end 
of the spring armature, but immedi- 
ately the circuit is broken and it 
flies back. These rapid vibrations ^ 
of the spring over the magnet, trans- 
mit similar impulses to the opposite 
end 'of the armature which forms 
the tread under the figure, and 
which results in many curious and 
grotesque steps being evolved for 
the amusement of the children. 



Novel Telephone Receiver. 

(No. 1,283,304; issued to Thomas 
Rhodus.) 
The receiver as shown is of the 
monocoil type, and the central iron 
core is secured to a flat base plate. 
In the improvement here shown, this 
base plate is formed with radial 
slits in its marginal portion to pro- 
vide a series of integrally connected 
sectors corresponding in number 
with the series of independent sec- 
tions which constitute tne outer an- 




nular pole-piece. This polcpietc 
comprises a series of radially dis- 
posed iron sections. The resistance 
of the coil is 75 ohms for tele- 
phonic work. 



Electromechanical Interrupter. 

(No. 1,282,388; issued to Francois 
de Cannart d'Hamale.) 
A unique electromechanical inter- 
rupter wherein the circuit is made 
and broken, not by virtue of an elec- 
tromagnet acting on an armature 
and pulling it away from a station- 
ary contact screw, but by means of 
a weighted auxiliary spring placed 
in a hermetically sealed compart- 
ment and acting by inertia. The 
weight supported at the top of the 
contact spring tends to keep on 
moving when the armature itself is 
suddenly stopt by striking against the 
magnet core, thus providing a very 
sudden break, which is highly desir- 
able for operating induction coils. 




Electric Lamp Fountain. 

(No. 1,280,784 ; issued to Matt 

Luckiesh.) 
* An electric lamp fountain op- 
erated by the heat radiated from 
an incandescent lamp placed in a 
confi'ned chamber in which there is 
an expansive fluid such as air. The 




inventor mentions that a 150-watt 
lamp has worked the apparatus. The 
liquid sprayed out thru the small 
capillary tube falls back into a sec- 
ond chamber, thru which the water 
can reach the inner chamber again 
thru a check valve. A thermostat 
may be used to make and break the 
circuit intermittently when desired. 
The cover of the fountain may be 
of glass and colored when preferred 
for the purpose of transmitting up- 
wardly thru the fountain spray a 
portion of the light from the lamp. 

Electric Phonograph. 

(No. 1,281,282; issued to Hans 
■ ^ Brockmiiller.) 

The idea is to provide a simple form 
of electric motor-driven phonograph 




with separable record turn-table and 
tone arm, so that for economical and 
other reasons it is not necessary 
to have a large special cabinet about 
the house. Any table can be quickly 
converted into a ffrst-class phono- 
graph by this scheme, the motor and 
a vertically driven shaft being se- 
cured underneath the table. The 
turn- table has a shaft which passes 
thru a hole in the top of the table, 
so as to engage the driving shaft 
frictionally. The tone arm has a 
special suction foot which does not 
require any screws, and the sound 
emanates around this foot. 



722 



ELECTRICAL EXPERIMENTER 



February, 1919 



dil 


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WK-. 


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^ Willi 


■ W^^lWk <fer 1 


J 



Our Amateur Laboratory Contest is open to all readers, whether subscribers or not. The photos are judged for best arrangement and efficiency of the appa- 
ratus. To increase the interest of this department we make it a rule not to publish photos of apparatus unaccompanied by that of the owner. Dark photos pre- 
ferred to light-toned ones. We pay $3.00 prize each month for the best photo. Address the Editor, "With the Amateurs" Dept. 



"Amateur Electrical Laboratory" Contest 

THIS MONTH'S $3.00 PRIZE WINNERS— F. L. BROOKS and W. P. CECIL 

THE accompanying photos are views of our Electro Chemical Laboratory and Radio Station (which is now closed). We have quite a number 
of electrical apparatus such as Oudin and Tesla coils, motors, spark coils, 12 volt storage battery, Leyden jars, electrolytic-interrupter Einthoven 
galvanometer — which was described in the Electrical Experimenter several months ago, 50 watt step-down transformer, also 200 watt 
transformer located behind switch-board and controlled by a five point switch, ammeter and voltmeter also on switch board, arc spot light which 
will throw a beam of light over a mile, small step-up transformer, condenser and spark gap. Our Chemical "Lab" consists of about S5 chemicals 
and about 15 pieces of apparatus such as test tnbes, Florence flasks, delivery tubes, hydrometer and other apparatus for carrying on experiments on 
a small 5calc. Last of all comes our work bench where everything has its beginning. We have a vise, gasoline blow torch, pliers, screw-drivers, 
twist drills and numerous other accessories. We also have a good supply of binding posts, screws, magnet wire, copper, brass and all such junk 
as is found in a red-headed bug's "Lab'* like my pal's, not saying anything of myself. — Floyd L. Brooks and Wm. P. Cecil. Ardmore, Oklahoma. 

HONORABLE MENTION (1 Year's Subscription to the **ELECTRICAL EXPERIMENTER'*) T. C. QUAYLE 

MY Chemical "Lab" consists of over 150 chemicals and reagents, also apparatus such as pipettes, burettes, retorts, test tubes, thistle tubes, 
delivery tubes, crucibles, casseroles, condensers, a Centigrade-Fahrenheit thermometer, chemists' scales, and many other pieces of laboratory 
glassware and apparatus, with which I carry on many interesting experiments in quantitative, qualitative and spectrum analysis. I also have gas, 
a Bunsen burner and a spigot for water in the "Lab". I have oyer 100 pieces of apparatus in my electrical "Lab", and have made a storage 
battery as described in the 1917 (Nov.) issue, also an arc searchlight, experimental arc furnace, magnetless buzzer, selenium cell (Bidwell type), 
Whcatstone bridge, electroscope, electrophorus, (sensitive) coherer, electrolytic rectifier and interrupter, Leyden jars, and many other pieces of 
apparatus described in the Electrical Experimenter. I also have an Oudin coil which is operated by an E. L Co. half kilowatt coil and a rotary 
spark gap of my own design, also 110 volt and battery motors, hand generator, hot wire ammeter, small storage cell, switches, fuse blocks, Geiss- 
ler tubes, etc. 

My work-shop is complete in tools for both wood and metal working and here is where I made the articles described in the "E. E." I 
have drills for both wood and metal, braces, chisels, files, saws, wrenches, planes, pincers, levels, two sets of taps and dies, one for small rods, 
tlic other for pipes; also an emery wheel and bench lathe, which I designed and built. — -Thomas C. Quayle, Berkeley, Cal. 




February, 1919 



ELECTRICAL EXPERIMENTER 



723 



Phoney Patents 



Under this heading are publisht electrical or mechanical ideas which 
our clever inventors, for reasons best known to themselves, have as yet 
not patented. We furthermore call attention to our celebrated Phoney 
Patent OfBzz for the relief of all suffering daffy inventors in this country 
as well as for the entire universe. 

We are revolutionizing the Patent business and OFFER YOU THREE 
DOLLARS ($3.00) FOR THE BEST PATENT. If you take your Phoney 
Patent to Washington, they charge you $20.00 for the initial fee and then 



you haven't a smell of a Patent yet. After they have allowed the Pat- 
ent, you must pay another $20.00 as a 5nal fee. That's $40,001 WE 
PAY YOU $3.00 and grant you a Phoney Patent in the bargain, so you 
save $43.00 ! ! When sending in your Phoney Patent application, 
be sure that it is as daffy as a lovesick bat. The daffier. the better. 
Simple sketches and short descriptions will help our staff of Phoney 
Patent Examiners to issue a Phoney Patent on your invention in a 

jiffy. 



HUN U BOAT UTILIZER 




Prize Winner; HUN U-BOAT UTILIZER. Particularly Adapted for Traffic Over Deserts. Take One Gyro Electric Destroyer a la Gerns- 
back, Knock Out All Machinery, Axles, etc., and Mount Plate Glass 16-inches Thick in Framework Covering Both Sides. Make Waterproof and 
Fill Cruiser with Pure Prohibition Liquid; Also one Hun Submarine. Weight of Submarine Pressing Against Sides, as Shown, Navigates 
Cruiser at Rate of 25 Knots an Hour with a Fair Zephyr Breeze Nor' by West. Inventor, Jose Matz, 300 Baker St., San Francisco, Cal. 

rSCREAM GENERATOR 







JK.V^. (^SA/S/ZATO fS 



I'SCREAM PARLOR GENERATOR. In Order to Save Tremendous Energy Now Going to Waste in All Ice-Cream Parlors, Due to Rotating 
Seats, My New Patent Provides Extending Shaft to the Rotating Seat, Which Shaft Operates Rotary Air Compressor. This Control Operates 
Air Tani<, Air Motor, Dynamo, etc. The Great Advantage to this Scheme Is That the Device Works Better the More Ice-Cream You Eat Be- 
cause of the Added Momentum. Separate Patent Application Provides to Charge Customers an Extra Nickel for Allowing Them to Spin 
Around. Hoover says Economize, Hence no Free Rides. Inventor, Garrett W. Lewis, Yuba City, Cal. 



724 



ELECTRICAL EXPERIMENTER 



February, 1919 




4. If a qu 
research work 
are answered. 



The "Oracle" is for the sole benefit of all electrical experimenters. Questions will be answered here for 
tlie benefit of all, but only matter of suflicient interest will be publisht. Rules under which questions will 
be answered: 

1. Only three questions can be submitted to be answered. 

-. Only one side of sheet to be written on; matter must be typewritten or else written in ink, no 
penciled matter considered. 

3. Sketches, diagrams, etc., must be on separate sheets. Questions addrest to this department cannot 
be answered by mail free of charge. 
ick answer is desired by mail, a nominal charge of 25 cents is made for each question. If the questions entail considerable 
or intricate calculations a special rate will be charged. Correspondents will be informed as to the fee before such questions 



HURLING THE VOICE ONE MILE. 

(979) W. J. M. asks: 

Q. 1. Is there any practical way of enor- 
mously amplifying the human voice so that 
same can be distinctly heard for a radius 
of, say, a mile, the atmosphere being com- 



Tocomp. arton.'\ 



Laid tolhing 
reproducer '; 



Micr 



Kk 





-lll!ll!li 



v^/ 



Comprest Air Loud Talker Such As Used On 
Phonographs, and Susceptible of Develop- 
ment For Hurling Voice Waves a Distance 
of One Mile. 

paratively free of other disturbances at the 
time? 

I understand that there are telephone 
transmitters now made for handling heavy 
currents of electricity. It occurs to me that 
possibly the above could be accomplisht by 
using such a transmitter in connection with 
a mammoth receiver and a suitable horn. 

A. 1. One of the leading phonograph 
companies have developed a verv' clever 
and powerful form of comprest air ampli- 
fier which we believe might be worked up 
on a sufficiently large scale to answer your 
requirements. In this system a low power 
aural or electrical voice signal is caused to 
act, by means of a relay or other appro- 
priate device, on an extremely sensitive 
valve, which p'ermits successive puffs of 




This Diagram Shows the Microphone Circuit 

For a 110 Volt D. C. Loud Talker. Having a 

Bank of 110 Volt Lamps in Series With the 

Reproducers. 

comprest air from a tank or bellows to 
pass out thru a large amplifying horn and 
reproducer. We also believe that the de 
Forest amplifier might solve your problem, 
as one model is capable of amplifying 
1,000,000 (one million) times. Also their 
Mr. Q. V. Logwood has stated that he be- 



lieves that your problem of amplifying the 
human voice so that it could be heard for 
a radius of one mile can be solved by mod- 
ern engineering design. He states that by 
means of microphones suitably connected 
to a large Oscillion bulb that he has actu- 
ally heard the human voice at a distance of 
one-half mile in California. 

The Alexanderson G. E. Co. magnetic 
amplifier should be of service to you in this 
connection. This clever and highly efficient 
magnetic amplifier was described in detail 



llllil 



■■llllllg 



: fill 



-11 



m ARTICLES SCHEDULED- FOR J 

J MARCH "E. E." m 

M "My Inventions" — No. 2 of a series J 

m by Dr. Nikola Tesla. Written exelu- J 

g sively for the Electrical Experi- H 

^ MENTER. g 

g "A Wonderful New Electric Ma- B 

W. chine that Sorts Tobacco Leaves by g 

H Size," by George Holmes. H 

H "How Powerful Electric Gyros H 

g Stabilice Ocean Ships" — Illustrated E 

g with excellent photos — by J. W. Hor- g 

J "Multiplex Telephony and Teleg- H 

B raphy and How It is Done," written g 

H by a Telephone Engineer. H 

g "Exploring Polar Regions and the J 

m North Pole by Airplane." g 

= "Locating Ore Bodies Underground H 

H by Electricity — A New Method." H 

J A New Talking Motion Picture H 

g Invention. g 

H "How Jimmy Saved the Bank" — A ■ 

H cracker-jack electrical story, by P. W. g 

B Russel. m 

= "Experiments in Radio-Activity — H 

= Part III," by Ivan Crawford. M 

H A Wavemetcr and Decremeter De- ■ 

W sign for Radio Students. Operators g 

g and Inspectors. With data on In- H 

H ductances, condensers, etc., by H. g 

H IVinfield Secor, Assoc. I. R. E. H 

H Practical Electro-plating, by Jo- J 

J seph Haas. g 

H "Efficient Radio Transmitting," by U 

I Donald H. Hassell. g 

g "Experiments With Ultra-Violet M 

J Light, for Amateurs," by J. C. M 

^ Morris, Jr. M 

llllliilllllllillillillllllllllllllllllillllllllllilllllilllilill 



in the April, 1916. issue of the Proceedings 
of the Institute of Radio Engineers. 

Several companies manufacture straight 
electro-magnetic systems of amplifying the 
voice, which systems are operated from 110 
volt circuits. We can supply names of 
these concerns on receipt of stamped en- 
velope. 

Relative to these systems, the Oracle 
Editor would say that he has heard the loud 
talkers put out by one of these concerns 
throw the voice a distance of from 800 to 
1,000 feet. The horns used are not over 2 



feet long in this system, but the inakers 
utilize special electro-magnetic reproducers 
which are connected in parallel when two or 
more are used, and these in turn are con- 
nected in series with a special microphone 
capable of operating on 110 volts D. C. and 
a bank of incandescent lamps. 



OUDIN COIL CONNECTION. 

_ (980) Forrest A. Miller, Shelbyville, 
Kentucky, writes : 

Q. 1. Asking several questions about 
Oudin and Tesla coils. 

A. 1. By means of high frequency Tesla 
or Oudin currents you can charge the body 
so as to emit sparks and charge other bodies 
or persons, etc., and you will find the ap- 
paratus and method of doing this com- 
pletely described in tlie book you are se- 
curing, viz. : "The Experimental Electricity 
Course" — which contains a special chapter 
on high frequency currents, with diagrams 



i/)i7/7f- IW/ 




Oud/ncoiJ 



Hook-Up For Spark Coil, Leyden Jars, Spark 
Gap, Oudin Coil and High Frequency Elec- 
trode For Giving So-Called Violet Ray Treat- 
ment. 

and full description of the apparatus used. 

We can also very highly recommend a 
book *jy Transtrom, entitled "Electricity 
at High Pressures and Frequencies" which 
our "Book Department" can supply at $2.15 
prepaid. 

The diagram herewith shows how a 
spark coil, Leyden jars, spark gap and 
Oudin type of high frequency coil are 
properly connected. The ground connec- 
tion is optional, but usually intensifies the 
unipolar discharge for electro-therapeutic 
requirements. 

SIX-INCH SPARK COIL DATA. 

(981) Marshall M. Wrenn, Baltimore, 
Md., asks the Oracle : 

Q. 1. For data on six-inch spark induc- 
tion coil. 

(Continued on page 726) 



February, 1919 



ELECTRICAL EXPERIMENTER 



725 



I 



Test Lesson In 

Draftsmanship 



Send for this free lesson which explains 
the Chicago "Tech" method of teaching 
Draftsmanship by mail. Positions at big 
salaries are now waiting for competent men. 
Even draftsmen of limited training and 
experience are snapped up and paid 
good salaries. If you are dissatisfied 
with your opportunities, learn Drafts- 
manship. Chicago "Tech" will train you 
in the most practical way in the short- 
est time. Mail the coupon today and 



let us tell you about 
the Chicago "Tech" 
method. The free 
lesson will show 
you how well 
equipped you are to 
follow Draftsmanship. 






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in the course only if you decide that you 
can take it up to advantage. No cost, 
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vestigation. Send the coupon. 



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Draftsmen always command v 
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on to meet vaBt foreiprn and increased do- 
meetic demands, the opportunities are g:reater 
than ever. This is the time for you to prepare 
for a better position— a higher salary. 

Come to the College or 

Learn At Home 

Hold you present position while training. Our experts will instruct 
you by mail. Only your spare time is required. You are directly under 
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required in the drafting rooms of big concerns. No time put in on un- 
necessary studies. This means thorough instruction and early graduation. 

Easy Payments 



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The fees for Chicago "Tech" Courses are very moderate — and you can pa 
terms. And also, you obtain in a few months what it would take 
several'years to acquire by ordinary methods. You can gst an early 
start, \ouare soon ready to take a paying position and to quickly 
get back the cost of your course. Then keep on earning more. 



y on easy 



FREE Instruments 

Every student of the Chicago "Tech" mail course in Draftsmanship receives 
this set of instruments, or a cash credit in case he already has a set. These 
instruments are of the same make and sizes as are used by high salaried 
experts in drafting rooms of factories, shops, railroads, etc. You use them 
while learning— then take them right into your practical work. ^ 



.4SlimKK'i*.'^ai | 



Auto and Gas Engine Course 

All about automobile mechanism— its construction, operation and REPAIR— 
taught by mail. You train directly under the Chicago "Tech" automobile ex- 
perts. Splendid opportunities open now. Send coupon and get all the facts. 

Learn All This in Spare Time 



Principle* of the Automobile. 

Every point made clear about the basic 
principles of propulsion— uteam, gas and 
electric cars. Power transmission syatcms 
in pleasure and commercial cars, etc. , L-tc. 

Gasoline Engines. All about the 
different types. A complete course in Raa 
enKine construction, operation and repair. 

Power Plants and Transmissions. 
Application of power by 4-6-8 12 cylinder 
enfcines. Types of clutcneo, sears, drives, 
axles, etc. 

Carburetors and Fuel Supply 
Systems. All methods demonstrated. 
Fuel values. Hnw to test Gasoline and 
air mixtures. Ke^ulation, care and man- 
a?eDient, etc.. etc , etc, 

Lubrication and Cooling All 



about oils and how to teat them. Splash 
and circulatinK systems . Operation in dif- 
ferent cars explained. Diaeramsand tables. 
Coolinif systems completely illustrated. etc. 

Batteries. Electrical principles ex- 
plained. Instructive diaRrama of wiring and 
connectioDB. Coils, condensers, vibrators, 
etc., etc. 

Magneto Ipnition. Principles and 
practic^ operation of various types and 
aystenja with diairrams. Generation of cur- 
rent. Field, armature, highand low tension, 
all explained. Complete in every point. 

Starting and Lighting Systems. 
All modern methods. Starters— spark , me- 
chanical, air. acetj;lene, electric, battery— 
shown in detail with diaifams and full ex- 
planations. Charging. Motor and gener- 
ator adjustments, etc., ■ 



Know How to Find and Fix Troubles 

Most complete instruction in auto rei.air work. Equips yon for hijrh pay or to start i 
^unineaa Btg demand fur trained repair men md men who know how to i 
'hia course makes you prnficient. Prepares you to take a job as an expert. 



iilable. 



to inapect cars. 
Not enough 

^^^^1^ T' I 'C* Send the coupon and get catalog and all information 
' ' *V£ A A_j about the Course, the small fee and the easy terms. 
All this sent on request. Mail coupon now. 



Send the Coupon — Now 

The sooner you are prepared the sooner you will be holding a job that pays a large salary 
and opens the way to advancement. Many executives, general managers and puperin- 
tendents began as draftsmen. 

Other institutions ask you to pay first— and then to find out later how well qualified 
you are for this profession. We send you the free lesson first and place you under no obli- 
gation at all. Discover your qualifications before you pay anything. 
The coupon 

I 

CHICAGO TECHNICAL COLLEGE, 

245 Chicago "Tech" Building, Chicago 

Without obligation to me, please send me your FREE Test Lesson and 
other interesting literature covering the subject indicated below. 
Mark X opposite work in which you are especially interested. 

D Architectural Drafting D Plan-Reading— Building 

n Machine Drafting D Plan-Reading— Shop Men 

n Electrical Drafting D Estimating 

D Structural Draftintr D Surveying 

n Sheet Metal Drafting D Map Drafting ~ 

D Builders' Course D Autos and Caa Engine" 



will bring theTest 
Lesson, free. Al- 
so information 
about the profes- 
sion of Drafts- 
manship and de- 
tailed facts about 
Chicago ■■Tech" 
methods, the fees, 
terms, etc. Mark 
with X the branch 
you are interested in 
—or if in doubt about 
which course to 
take, write a letter 
stating facts about 
yourself and asking 
our advice which 
will be freely given. 
Mail either the cou- 
pon or letter today. 



Chicago Technical College 



24S Chicago "Tech" Bids. 
Chicago, 111. 



I College or Home Study? State which.. 



You benefit by mentioning the "Electrical Experimenter" when writing to advertisers. 



726 



ELECTRICAL EXPERIMENTER 



Feb 



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THE ORACLE, _ 

(Contiuucd from page 724) 

A, 1. We give you herewith necessary 
information for constructing a six-inch 
jump spark coil : 

Primary, 220 ft. No. 13 D. C C. wire. 

Secondary, 7 lbs. No. 36 double silk cov- 
ered wire (or enameled). 

Core, 1% X 14" soft iron wire (thoroly 
annealed). 

The primao' condenser to be connected 
across the vibrator should comprise 4,500 
sq. in. tinfoil, cut in suitable size slicets and 
interspersed between slightly larger paraf- 
fined paper sheets. If an electrolytic inter- 
rupter is used on 110 volts A. C. or D. C, 
then no primary condenser is necessary. 

There should be a hard rubber insulating 
tube between the primary and secondary 
coils. The dimensions of this tube are 
14^" X 1^" outside diameter by %" viaU. 
The secondary consists of thirty-eight 
pies, each Vwth" thick, having an outside 
diameter of 4}4". There should be placed 
between each section six pieces of well- 
soaked paraffin paper. 

An excellent book dealing exclusively on 
spark coils building can be procured from 
our "Book Department" for $3.00. The 
title of this book is "Design and Construc- 
tion of Induction Coils," by Collins. In 
this book there is given all the details for 
the construction of spark coils such as core 
dimensions, size of wire, length of pri- 
maries, etc. 



DATA ON WIRELESS POWER 
TRANSMISSION. 

(982) John Verrge, Detroit, Michigan, 
writes the "Oracle" : 

Q. 1. The sketch herewith shows my 
idea on the wireless transmission of power. 
Where can I find engineering data on the 
design of such a system? How can I figure 
the voltage required to transmit a given 
kilowattape over a certain distance? etc., 
etc. 

A. 1. We have examined your query, to- 
gether with diagram showing your ideas 
for the wireless transmission of power to 
electric railway cars, etc. 

We regret to say that there is at the 
present time no engineering data available 
for solving the problems you outline, as 
while Nikola Tesla has successfully lighted 
lamps and operated motors by the one wire 
and no-wire wireless system for distances 
of 15 miles in his famous Colorado experi- 
ments, this branch of advanced alternating 
current engineering has not been made 
available in text-book form as yet. 

You would do well to visit your public 
library and look up Dr. Tesla's book, eiiti- 
tled "Experiments with Currents of High 
Potential and 1-requency". 




and tables given greatly facilitate and simplify 
the calculation of field and other magnet windings, 
and it is wiitten so clearly that any electrician or 
student can grasp the simple arithmetic involved 
after once reading it. An appendix of useful 
tables is given at the end of the book which will 
prove of great value in conjunction with the work 
treated upon. 

PRACTICAL FLYING, by Flight Com- 
mander W. G. McMinnies, R. N. Cloth 
covers, 246 pages, profusely illustrated, 
size Syi X 8J4 inches. Price $1.50. Pub- 
lisht by George H. Doran Company, New 
York, N. Y. 

An excellent course on flying instruction which 
is very ably illustrated by comprehensive sketches 
in plan and perspective, showing all of the parts 
of modern battle and scout 'planes, and giving 
from start to finish all of the necessary elements, 
including the reading of maps and the determina 
tion of location while in the air. This book, con- 
trary to most semi-technical or technical treatises, 
is one that any aviator or flying enthusiast can 
read with extreme pleasure and at the same time 
greatly improve his understanding of the heavier- 
than-air flying machine. The author has the title 
of Flight-Commander of the British Royal Navy 
and knows whereof he speaks. 

The chapters are subdivided under departmental 
heads, so that the book forms a very excellent 
reference work, as well as a classroom and gen- 
eral reading volume. Flight Commander McMin- 
nies treats the subject in a very broad way and 
covers such points as — "which men make good 
pilots"; in this chapter he evidences a good grasp 
of the subject of applied psychology. As we pass 
along thru the elementary studies of the airplane 
and its component parts, we find the text and 
drawings so interesting, that it does not tire us at 
all. 

Some very excellent diagrams and drawings are 
given, showing the various accidents in landing 
and how they occur, also how all the fancy 
"stunts" are performed progressively in the air. 
The sections treating on cross-country flying and 
the determination of altitude as well as orienta- 
tion, are clearly written and treated on in a 
manner following that found most efficient by the 
Allied fliers on the Western front. 



PRACTICAL ARMATURE AND MAG- 
NET WINDING, by Horstmann & 
Toiiscly. Leather covers, 252 pages, 128 
illustrations, size 4^ x 6^ inches. 
Price $L00 in cloth; $L50 in leather. 
Pnblisht by Frederick J. Drake & Co., 
Chicago. 

This is a handbook for the practical electrician, 
especially those performing shop work and en- 
gaged in dynamo and motor repairs. The authors 
give the principles with special and clearly drawn 
illustrations of the elements of armature design, 
armature windings and the mechanical features 
such as balancing and ventilation of different 
types of armatures, etc. The section on armature 
windings is quite complete and gives all necessary 
information for laying out drum and lap wind- 
ings, and for different numbers of field poles. 
The authors then give a discussion on armature 
troubles and testing for faults in the windings, 
armature calculations with wire tables, alternating 
current windings, et cetera. One of the most 
interesting sections of the work is thai on field 
magnet winding, and of course this applies to 
magnet windings of any type. The special formulas 



GENERAL LECTURES ON ELEC- 
TRICAL ENGINEERING, by Charles 
Proteus Steinmetz. Cloth covers, 242 
pages, 50 illustrations, size 6J4 x 9}^ 
inches. Price $2.50. Publisht by Mc- 
Graw-Hill Book Company, Inc., New 
York, N. Y. 

This volume contains some of the most interest- 
ing lectures given by Vt. Steinmetz, and forms a 
most valuable work which will find a welcome in 
the library of every engineer, electrical man and 
student. Dr. Steinmetz is a speaker and writer 
of articles which possess great expanse of view- 
point. When he speaks of the incandescent lamp, 
for instance, in lecture 16 of this series here 
presented, the reader will be surprised at the wide 
range of topics he discusses. Practically every 
important type of lamp and their relative operat- 
ing efficiencies and characteristics are treated 
upon in this lecture, even down to the modern 
gas-filled Maztia tungsten lamp. The several other 
lectures, of which tnere are 18 in all, cover such 
interesting and important subjects as electrochem- 
istry, the alternating current railway motor, elec- 
tric railways, lightning protection, direct current 
regulation and control, hunting and synchronous 
machines, high frequency oscillations, surges and 
impulses, higher harmonics of the generator wave, 
long distance transmission, arc lighting, modern 
power generation, etc., etc. 



STANDARD WIRING FOR ELECTRIC 
LIGHT AND POWER, by H. C. Gush- 
ing, Jr. Leather covers, 300 pages, pro- 
fusely illustrated, size 6J4 x 4% inches. 
Price $1,50. Publisht by H. C. Gushing, 
Jr., 1918, New York, N. Y. 

One of the most widely read and also one of the 
most clearly written and easily understood works 
available to electrical men in all branches of the 
industry. Mr. Cushing's manual has been useful 
for many years. Each year a new edition is 
brought out covering the latest changes in the 
Fire Underwriter's rules. The author follows the 
Underwriter's rules and describes with the aid of 
simple formulas, numerous tables, and special il- 
lustrations, the exact meaning of the various 
clauses in the wiring code, so that this book be- 
comes very valuable to electricians, architects, 
superintendents and engineers. Some of the sim- 
plest tables and methods of using them for cal- 
culating both H^ht and power distribution wiring 
ever j^iven are included in this manual, and any 
electrical man can understand them easily. A 
number of diagrams of electric motor connections, 
including series, shunt and compound machines, 
are given as well as instructions for the proper 
installation of all such machinery. House wiring 
receives special attention all the way thru the 
work, and electrical wiremen will find this manual 
a most useful and authoritative companion. It 
settles all wiring disputes. 



You benefit by mentioning the "Electrical Experimenter" when writing to advertisers. 



February. 1919 



ELECTRICAL EXPERIMENTER 



727 



Leairii ElectFicit 



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These courses are thorough, short and practical. All instruction given on 
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The War is Over — Yes I 

but the men "over there" will not be back 
for months — perhaps years, for their work 
"over there" isn't over. And so you. and thou- 
sands more must fill up the gap now that the 
absence of these brave workers has made in the 
ranks of skilled labor. Trained Electricians are 
needed more, perhaps, than any other class of men. 
The sudden ending of the war has caused the big indus- 
tries to start up work sooner than any of us expected and 
in consequence the Manufacturers are Calling for Trained 
Men, and we are training men as fast as we can to meet 
these urgent calls. You are needed. Young Man, now! 
Don't wait. Don't put it off. 'iei in touch with us Today. 
Get ready to join the great "Peace Army" here at home. 
Your country calls. Again we say, prepare to serve your 
country! We'll make a trained electrician of you in three 
months! Let's go! 



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Skilled Draftsmen are always in demand. Our courses 
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728 



ELECTRICAL EXPERIMENTER 



February, 1919 




BE A BOY CHEMIST 

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West of Mississippi Birer and in Canada — $6.00 

Be sure you get "CHEMCRAFT," the original 
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The Electric Safety razor makes shaving a 
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A home u.ier savs — "The most pleasing shave I've 
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Write for llla<»traiftd circular describiiig Lek-Tro- 
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Famous Scientific Illusions 




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{Continued from page 694) 



The earliest trials were made by Dali- 
brand in France, but Franklin himself was 
the first to obtain a spark by using a kite, in 
June, 1752. When these atmospheric dis- 
charges manifest themselves today in our 
wireless station we feel annoyed and wish 
that they would stop, but to the man who 
discovered them they brought tears of joj'. 



latter has the property of quickly dissipat- 
ing the accumulated char.cte into the air. 
To examine this action in the light of pres- 
ent knowledge we may liken electric poten- 
tial to temperature. Imagine that sphere j 
is heated to T degrees and that the pin or 
metal bar is a perfect conductor of heat so 
that its extreme end is at the same tem- 




//y.7 



The Theory Has Bean Seriously Advanced and Taught that the Radio Ether Wave 
Osciiiatlons Pass Around the Earth by Successive Reflections, as Here Shown. The 
Efficiency of Such a Reflector Cannot he more than 25 Per Cent: the Amount of 
Energy Recoverable in a 12,000-mile Transmission being but One Hundred and Fif- 
teen Billionth Part of One Watt, with 1,000 Kilowatts at the Transmitter. 



The lightning conductor in its classical 
form was invented by Benjamin Franklin 
in 1755 and immediately upon its adoption 
proved a success to a degree. As usual, 
however, its virtues were often exagger- 
ated. So, for instance, it was seriously 
claimed that in the city of Piatermaritz- 
burg (capital of Natal, South Africa) no 
lightning strokes occurred after the pointed 
rods were installed, altho the storms were 
as frequent as before. Experience has 
shown that just the opposite is true. _A 
modern city like New York, presenting in- 
numerable sharp points and projections in 
good contact with the earth, is struck much 
more often than equivalent area of land. 
Statistical records, carefully compiled and 
publisht from time to time, demonstrate 
that the danger from lightning to property 
and life has been reduced to a small per- 
centage by Franklin's invention, but the 
damage by fire amounts, nevertheless, to 
several million dollars annually. It is as- 
tonishing that this device, which has been 
in universal use for more than one century 
and a half, should be found to involve a 
gross fallacy in design and construction 
which impairs its usefulness and may even 
render its employment hazardous under cer- 
tain conditions. 

For explanation of this curious fact I 
may first refer to Fig. 3, in which .s is a 
metallic sphere of radius r, such as the ca- 
pacity terminal of a static machine, pro- 
vided with a sharply pointed pin of length 
/i. as indicated. It is well known that the 



perature T. Then if another sphere of 
larger radius, v\, is drawn about the first 
and the temperature along this boundary is 
7"i, it is evident that there will be between 
the end of the bar and its surrounding a 
difference of temperature T — Ti, which 
will determine the outflow of heat. Obvi- 
ously, if the adjacent medium was not af- 
fected by the hot sphere this temperature 
difference would be greater and more heat 
would be given off. Exactly so in the elec- 
tric system. Let q be the quantity of the 
charge, then the sphere — and owing to its 
great conductivity also the pin — will be at 

q 

the potential — . The medium around the 

r 
point of the pin will be at the potential 

q q 

and, consequently, the differ- 



r-l-h 

q q 



qh 



ence . Suppose now 

r r-fh r(r-l-h) 
that a sphere 5" of much larger radius 
R = nr is employed containing a charge Q 
this difference of potential will be, analog- 

Qh 

ously . Accordmg to elementary 

.R(R+h) •* 

prmciples of electro-statics the potentials 
of the two spheres j and 5" will be equal if 

Qh 
Q = nq in which case =; 

RCR-fh) 
{Continued on page 730) 



You benefit by mentioning the "Electrical Experimenter" -when writing to advertistrs. 



I 



February, 1919 



ELECTRICAL EXPERIMENTER 



729 



"Here's an Extra $50, Grace 

— rm making real money now!*' 

"Yes, I've been keeping it a secret until pay day came. I've been pro- 
moted with an increase of $50 a month. And the first extra money is 
yours. Just a little reward for urging me to study at home. The boss 
says my spare time training has made me a valuable man to the firm and 
there's more money coming soon. We're starting up easy street, Grace, 
thanks to you and the I. C. S.!" 

Today more than ever before, money is what counts. The cost of living is mounting 
month by month. You can't get along on what you have been making. Somehow, 
you've simply got to increase your earnings. 

Fortunately for you hundreds of thousands of other men have proved there is an 
unfailing way to do it. Train yourself for bigger work, learn to do some one thing well 
and employers will be glad to pay you real money for your special knowledge. 

You can get the training that will prepare you for the i t.-routhcr,: 

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BOX 6173, SCRANTON.PA. 

Explain, without obligating me, tiow 1 can qualify for the pOBl- 
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FLECTKICAL ENGINEER 

Electrician 

^Electric Wiring 
^Electric Lighting 
I^EIectric Car Running 
3 Heavy Electric Trai'tion 
H Electrical Draftsmai 
^Electric Machine Designer 
3 Telegraph Expert 
3 Practical Telephony 
3 MECIIANU'Al. KNdlNEEIt 
I] Mechanical Drafrsman 
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H Machine Shop Practice 
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Show Card Writer 
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n ILLUSTRATOR 

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Stenographer and Typist 
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730 



ELECTRICAL EXPERIMENTER 



February, 1919 



Mesco Telegraph 
Practice Set 

For Learning Telegraph Codes 




The Practice Set comprlaes a regular tele- 
graph key, without circuit breaker, a special 
bigb pitch buzzer, one cell Red Seal Dry 
Battery, and four feet of green silk covered 
flexible cord. 

The key and buzzer are mounted on a 
highly finished wood base, and three nickel 
plated binding posts are so connected that the 
set may be used for five different purposes. 
List No. Price 
342 Telegraph Practice Set, with Bat- 
tery and Cord $3.24 

Weighs 4 lbs. packed. 

Price does not include postage. 

C«iBbciuH«i Placlicc Set for levnin; Ibc Motm 
■j>d C«aliK0lil Vtsut ud Audible Cades 



MESCO 




ThU oatflt Is the only reliable Instrument which 

win enable Btudent* to become proaclent operator* 

In tbe U. 8. Ntral Serrloe. beciose It U ©Quipped 

with a tnuzer and miniature lamp enabling the 

Qser to maater both tbe rlsual and audible eUcnala 

quickly. 

Lilt No. 52— PracUce Set with Red Seal Bat- 

tery and Cord $4.05 

Waloha4 Iba. Melted. Price doe* not inotude poetaga. 

Send for the New Edition of 
Our Catalog W28 

It li aoeket size. conUlne 248 page*, with ovar 
1.000 iMuttratlont. and detcrlbei In plain, clear 
language all about Belli. Puth Buttoni. Bitlerlea. 
Telephone and Tel»ffrapn Material. Electric Toy*. 
Burglar and Fire Alarm Contrivances. Electrlo Call 
Belli. Electric Alarm Clocks. Medical Batteries. 
Motor Boit Horns, Electrically Heated Apparatus. 
Battery Connector*. SwttcSei, Battery Gausee, 
Wlreleea Telegraph Instruments, Ignition Supplies, 
eu. 

Send for the Catalog Now 

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Supply Com Inc. 

NEW YORK: CHICAGO: ST. LOUIS: 

17 Park Place 114 8, WeUa St. 1108 Pine St. 

San Franeltco Offloe: 604 Mltslon St. 



MECHANICALLY RIGHT— A REAL LATHE 

A Regular lathe, not a toy 



Swlnir 4 Inches, 11 Inches between cen- 
ters. 17 Inches total letiRth. Net weight 
9 lbs. eOilpplng weight 13 Ibe. 
The bed of this lathe la machined. 
Workmanship is tint class througnout. 
Lathe comes cquipp<:d with wood turn- 
ing chuck. Lathe can be fitted with 3 

inch face plate and drill chuck as special eaulpment. 

Order one today. Price S5.D0 cash with order. 

SYPHER MFG. CO., Dept. C, TOLEDO, OHIO 

Feldman's "Geyser" 
Electric Water Heater 

Irutantaneout Hot Water 

FELDMAN MFG. CO. 

1500 Times Bldg. New York City 

HAVE You SENT 

for our booklet No. 4, glvinK diagrams and erpcri- 

ments with the Steco Button ? 
STECO. 2134 N. Clark St.. Chicago, III. 



FAMOUS SCIENTIFIC ILLUSIONS. 

{Continued from page 728) 

nqh qh 
=: . . Thus the dif- 



nr(nr + h) r(nr + h) 

ference of potential between the point of 

the pin and the medium around the same 





Fig. 4, Tesia Explains the Fallacy of the 
Frant<lln Pointed Lightning Rod, Here Illus- 
trated, and Shows that Usually Such a Rod 
Could Not Draw Off the Electricity in a Sin- 
gle Cloud In Many Years. The Density of the 
Dots Indicates the Intensity of the Charges. 



will be smaller in the ratio 



r + h 



when 



nr +h 

the large sphere is used. In many scientific 
tests and experiments this important ob- 
servation has been disregarded with the 
result of causing serious errors. Its sig- 
nificance is that the behavior of the 
pointed rod entirely depends on the linear 
dimensions of the electrified body. Its 
quality to give off the charge may be en- 
tirely lost if the latter is ver>' large. For 
this reason, all points or projections on the 
surface of a conductor of such vast dimen- 
sions as the earth would be quite ineffective 
were it not for other influences. These 
will be elucidated with reference to Fig. 4, 
in which our artist of the Impressionist 
school has emphasized Franklin's notion 
that his rod was drawing electricity from 
the clouds. If the earth were not sur- 
rounded by an atmosphere which is gener- 
ally oppositely charged it would behave, 
despite all its irregularities of surface, like 
a polished sphere. But owing to the elec- 
trified masses of air and cloud the distribu- 
tion is greatly modified. Thus in Fig. 4, 



the positive charge of the cloud induces in 
the earth an equivalent opposite charge, the 
density at the surface of the latter dimin- 
ishing with the cube of the distance from 
the static center of the cloud. A brush 
discharge is then formed at the point of the 
rod and the action Franklin anticipated 
takes place. In addition, the surrounding 
air is ionized and rendered conducting and, 
eventually, a bolt may hit the building or 
some other object in the vicinity. The vir- 
tue of the pointed end to dissipate the 
charge, which was uppermost in Franklin's 
mind is, however, infinitesimal. Careful 
measurements show that it would take 
many years before the electricity stored in 
a single cloud of moderate sice would be 
dra-um off or neutralized thru such a light- 
ning conductor. The grounded rod has the 
quality of rendering harmless most of the 
strokes it receives, tho occasionally the 
charge is diverted with damaging results. 
But, what is very important to note, it 
invites danger and hazard on account of 
the fallacy involved in its design. The 
sharp point which was thought advantage- 
ous and indispensable to its operation, is 
really a defect detracting considerably from 
the practical value of the device. I have 
produced a much improved form of light- 
ning protector characterized by the employ- 
ment of a terminal of considerable area and 
large radius of curvature which makes im- 
possible undue density of the charge and 
ionization of the air.* These protectors 
act as quasi-repcllents and so far have 
never been struck tho exposed a long time. 
Their safety is experimentally demon- 
strated to greatly exceed that invented by 
Franklin. By their use property worth 
millions of dollars which is now annually 
lost, can be saved. 

III. The Singular Misconception of the 
Wireless. 

To the popular mind this sensational ad- 
vance conveys the impression of a single 
invention but in reality it is an art, the suc- 
cessful practise of which involves the em- 
ployment of a great many discoveries and 
improvements. I viewed it as such when I 
undertook to solve wireless problems and 
it is due to this fact that my insight into its 
underlying principles was clear from their 
very inception. 

In the course of development of my in- 
duction motors it became desirable to op- 
erate them at high speeds and for this pur- 
pose I constructed alternators of relatively 

•Reftr to the October, 1918, issue of this jour- 
nal wherein Dr. Testa's new form of non-pointed 
lightning rod was fully described and illustrated. 

(Conlinurd on page 732) 




Diagram Used to Explain the Fallacy of the Franklin Pointed Lightning Rod, and an 
Analogy Whereby the Author Shows In a Clear Manner How the Charged Sphere May 
for Illustration be Considered as Heated to a High Degree, and the Heat Allowed to 

Escape at a Known Rate 



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r 



February, 1919 



ELECTRICAL EXPERIMENTER 




Taught By A Practical Man 

and in Your Home! 



' ^^- IT IS UP TO YOU 

I am teaching electricity and drafting to many men, young and old, and ladles too, and wish 
to interest you sufficiently so you will send for my catalog which tells the whole story, as It is too 
much to tell here. It is up to you whether you look into the proposition, but if you are earnest In 
your desire to get into the electrical industry, or to become more proficient in this line, you will 
send for the catalog and you will not regret the time you give in doing so. 

THE PURPOSE OF THE COURSE OF STUDY 

I have been lieaigniiig courses in electrical instruction anri teacliinq electricity, nff and on during the 
past 17 years, and durint: that time I have had an unusual omwtunity to make a sneoial study of the leachmg 
business, from the slaiulpoint of a practical man. This course of my own is desiBned with a view of reacluiii; th'>se 
who r?o not have a lot nf time and money to devote to <itudy work, and to cive them ii« Hinrongh a knowlodjie 
as possible of electricity, in the shortest T.ossible time. The instruction is given like von were working on various jotw and I was the boss telling you what to d" 
and how to do it, and giving the explanation necessary for the understanding of the theoi-y covered by the dubjocl under discussion. There are many conditions 
which seldom occur in the every day run of electrical experience, and these conditions 1 lay particular stress on. This part of the instruction makes the course 
particularly attractive and valuable to those already engaged in active electrical work. 

FIFTY FIFTY 

I work absolutely on a 50-50 basis with ray students. You pay me the comparatively low price 1 ask. and I give you the instruction and other help a-i 
l3 stated in my catalog. No student is pernjitted to rav cash for his entire^ course on starting, the course being paid for in small monthly payments as 
you go along. Students have the prlvili>ge of discontinuing the work if they should find that it was not just what they were after, and their payments stop 
at the same time. Tliia is my way of doiii- business and I would not want yourmoney when I was not giving you the instruction. 

Apparatus, Instruments, Material, Etc. J" l8«i<|3i",'',U¥R,cAL school. 

Certain electrical apparatus, instruments, material, cliarts, drafting implements, ■ 745 East 42nd Street Chicago Illinois. 
etc., as detailed in the catalog, are included in the course and are a part of tlie 

regular instruction for which there is no extra charge as it is covered by the reg- | t>entlenien: 
ular montljJy payments. Send me catalog describing your course in Electricity and Drafting. 

FILL OUT COUPON FOR ONE OF MY CATALOGS WHICH GIVES FULL | wamit 
INFORMATION. NAMi. 

BURGESS ELECTRICAL SCHOOL ' c^'^'^:;;;:!::;;;;:;:::;;;;:;;;;;:::;";!!:^;:::;;;;;;:;;;;:';; 

745 E. 42d Street Chicago, 111. ' state'' !"! 



To Practical Men and Electrical Students: 



{See review of this book by Editor in December issue of your Electrical Experimenter, page 568) 



I have prepared a pocket-size note book espe- 
cially for the practical man and those who are 
taking up the study of electricity. It contains 
drawings and diagrams of electrical machinery and 
connections, over two hundred formulas for calcu- 
lations, and problems worked out showing how 
the formulas are used. This data is taken from 
my personal note book, which was made while on 
different kinds of work, and I am sure it will be 
found of value to anyone engaged in the electrical 
business. 

The drawings of connections for electrical appa- 
ratus include Motor Starters and Starting Boxes, 
Overload and Underload Release Boxes, Revers- 
able Types, Elevator Controllers, Tank Controllers, 
Starters for Printing Press Motors, Automatic 
Controllers, Variable Field Type, Controllers for 
Mine Locomotives, Street Car Controllers, Connec- 
tions for reversing Switches, Motor and Dynamo 
Rules and Rules for Speed Regulation. Also, 
Connections for Induction Motors and Starters, 
Delta and Star Connections and Connections for 
Auto Transformers, and Transformers for Lighting 
and Power Purposes. The drawings also show all 
kinds of lighting circuits, including special controls 
where Three and Four Way Switches are used. 

The work on Calculations consist of Simple 
Electrical Mathematics, Electrical Units, Electrical 



Connections, Calculating Unknown Resistances, 
Calculation of Current in Branches of Parallel 
Circuits, How to Figure Weight of Wire, Wire 
Gauge Rules, Ohm's Law, Watt's Law, Informa- 
tion regarding Wire used for Electrical Pur- 
poses, Wire Calculations, Wiring Calculations, 
Illumination Calculations, Shunt Instruments and 
How to Calculate Resistance of Shunts, Power 
Calculations, Efficiency Calculations, Measuring 
Unknown Resistances, Dynamo and Dynamo 
Troubles, Motors and Motor Troubles, and Calcu- 
lating Size of Pulleys. 

Also Alternating Current Calculations in finding 
Impedance, Reactance, Inductance, Frequency, 
Alternations, Speed of Alternators and Motors, 
Number of Poles in Alternators or Motors, Con- 
ductance, Susceptance, Admittance, Angle of Lag 
and Power Factor, and formulas for use with Line 
Transformers. 

The book called the "Burgess Blue Book" is 
published and sold by the Burgess Engineering 
Company foj: one dollar ($1.00) per copy, post- 
paid. If you wish one of the books, send me your 
order with a dollar bill, check or money order. 
I know the value of the book and can guarantee 
its satisfaction to you by returning your money if 
you decide not to keep it after having had it for 
five days. 



BURGESS ENGINEERING CO., 



Yorke Burgess, Consulting Engineer 

747 East 42nd Street Chicago, Illinois 



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732 



' Ymu can be quickly cured, if yoa 



'STAMMER 



/i 

m Send 10 cents coin or stamps tor Tt*-pat?e book on Stain- 
m merintraiKl Stuttering. "llsCaascaadCvc." It tells how I 
^M cared ni>-3e'.f after stamroering for 20 years. 

^ Benjamin N. Bogue, 751 Bogve Boildiog, lo£uapoIis 

i^^n'rirof NIKOLA TESLAil!! 

M • We have prepared a genuine, 
^ handsome photograph, auto- 
(^ graphed in facsimile by the great 
^ inventor. This photograph, taken 
^ in December, 1918, was posed 

^ especially for the cover design ^ 

^ of the JFebruary, 1919, issue of ^ 

Uk the "Electrical Experimenter". It Uk 

jn shows Tesla as he is today, hold- JR 

!■ ing his famous wireless-lighted ja 

^ globe. No advertising whatso- ^ 

(gt ever on this photo, except for the ilk 

^ autograph. Size about 9 x 12". ^ 

(ft Ready for framing. A striking W 

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EXPERIMENTER PUBLISHING CO ^ 

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ELECTRICAL EXPERIMENTER 

FAMOUS SCIENTIFIC ILLUSIONS 

(^Coni'mucd from page 730) 
high frequencies. The striking behavior of 
the currents soon captivated my attention 
and in 1889 I started a systematic investi- 
gation of their properties and the possibili- 
ties of practical application. The first 
gratifying result of my efiforts in this direc- 
tion was the transmission of electrical 
energj' thru one zvirc without return, of 
which I gave demonstrations in my lectures 
and addresses before several scientific 
bodies here and abroad in 1891 and 1892. 
During that period, while working with my 
oscillation transformers and dynamos of 
frequencies up to 200,000 cycles per second, 
the idea graduallj" took hold of me that the 
earth might be used in place of the wire, 
thus dispensing with artificial conductors 
altogether. The immensity of the globe 
seemed an unsurmountable obstacle but 
after a prolonged study of the subject I 
became satisfied that the undertaking was 
rational, and in my lectures before the 
Franklin Institute and National Electric 
Light Association early in 1893 I gave tlie 
outline of the system 1 had conceived. In 
the latter part of that year, at the Chicago 
World's Fair, I had the good fortune of 
meeting Prof. Helmholtz to whom I ex- 
plained my plan, illustrating it with experi- 
ments. On that occasion I asked the cele- 



Wireless Stations Will Shortly Re-open 

Date, only, uncertain 
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necessity of securing licenses for transmitting sets with a range beyond the 
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Please do not write for catalog If you have No. 11. Paper costs three times as much as formerly. 
Let the amateur without a catalog secure one. Write for prices In advance. Just now we have no 
price llat, because the changes have been so frequent. Will advise through this magazine when re- 
vised price list Is ready, which will be as quickly as possible. 

C__J 0-. In coin or stamps today for oui bU 300 page No. 11 Electrical and Wlreleaa Catalog. Any 
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MAGNETIC 
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Write for bulletin No. 12 today. 

The French Manufacturing Company 

Cleveland, Ohio U. S. A. 



February, 1919 

brated physicist for an expression of opin- 
ion on the feasibility of the scheme. He 
stated unhesitatingly that it was practicable, 
provided I could perfect apparatus capable 
of putting it into effect but this, he antici- 
pated, would be e.xtremely difficult to ac- 
complish. 

I resumed the work very much encour- 
aged and from that date to 1896 advanced 
slowly but steadily, making a number of 
improvements the chief of which was my 
system of concatenated tuned circuits and 
method of regulation, now universally 
adopted. In the summer of 1897 Lord 
Kelvin happened to pass thru New York 
and honored me by a visit to my laboratory 
where I entertained him with demonstra- 
tions in support of my wireless theory. He 
was fairly carried away with what he saw 
but, nevertheless, condemned tny project in 
emphatic terms, qualifying it as something 
impossible, "an illusion and a snare." I 
had expected his approval and was pained 
and surprised. But the next day he re- 
turned and gave me a better opportunity 
for explanation of the advances I had made 
and of the true principles underlying the 
system I had evolved. Suddenly he re- 
marked with evident astonishment: "Then 
you are not making use of Hertz waves?" 
"Certainly not," I replied, "these are radia- 
tions. No energy could be economically 
transmitted to a distance by any such 
agency. In my system the process is one 
of true conduction which, theoretically, can 
be effected at the greatest distance without 
appreciable loss." I can never forget the 
magic change that came over the illustrious 
philosopher the moment he freed himself 
from that erroneous impression. The skep- 
tic who would not believe was suddenly 
trarisformed into the warmest of support- 
ers. He parted from me not only thoroly 
convinced of the scientific soundness of the 
idea but strongly e.xprest his confidence in 
its success. In my exposition to him I re- 
sorted to the following mechanical ana- 
logues of my own ancl the Hertz wave 
system. 

Imagine the earth to be a bag of rubber 
filled with water, a small quantity of which 
is periodically forced in and out of the 
same by means of a reciprocating pump, as 
illustrated. If the strokes of the latter are 
effected in intervals of more than one hour 
and forty-eight minutes, sufficient for the 
transmission of the impulse thru the whole 
mass, the entire bag will expand and con- 
tract and corresponding movements will be 
imparted to pressure gauges or movable 
pistons with the same intensity, irrespective 
of distance. By working the pump faster, 
shorter waves will be produced which, on 
reaching the opposite end of the bag, may 
be reflected and give rise to stationary 
nodes and loops, but in any case, the fluid 
being incompressible, its inclosure perfectly 
elastic, and the frequency of oscillations 
not very high, the energy will be economic- 
ally transmitted and very little power con- 
sumed so long as no work is done in the 
receivers. This is a crude but correct rep- 
resentation of my wireless system in which, 
however, I resort to various refinements. 
Thus, for instance, the pump is made part 
of a resonant system of great inertia, 
enormously magnifying the force of the 
imprest impulses. The receiving devices 
are similarly conditioned and in this man- 
ner the amount of energy collected in them 
vastly increased. 

The Hertz wave system is in many re- 
spects the very opposite of this. To ex- 
plain it by analogy, the piston of the pump 
is assumed to vibrate to and fro at a ter- 
rific rate and the orifice thru which the 
fluid passes in and out of the cylinder is 
reduced to a small hole. There is scarcely 
any movement of the fluid and almost the 
whole work performed results in the pro- 
duction of radiant heat, of which an in- 
finitesimal part is recovered in a remote 
locality. However incredible, it is true that 



Yoit benefit by mentioning the "Electrical Experimenter" when writing to advertisers. 



February, 1919 

the minds of some of the ablest experts 
have been from the beginning, and still 
are, obsest by this monstrous idea, and so 
it comes that the true wireless art, to which 
I laid the foundation in 1893, has been re- 
tarded in its development for twenty years. 
This is the reason why the "statics" have 
proved unconquerable, why the wireless 
shares are of little value and why the Gov- 
ernment has been compelled to interfere. 

We are living on a planet of well-nigh in- 
conceivable dimensions, surrounded by a 
layer of insulating air above which is a 
rarefied and conducting atmosphere (Fig. 
5). This is providential, for if all the air 
were conducting the transmission of elec- 
trical energy thru the natural media would 
be impossible. My early esperiments have 
shown that currents of high frequency and 
great tension readily pass thru an atmos- 
phere but moderately rarefied, so that the 
insulating stratum is reduced to a srnall 
thickness as will be evident by inspection 
of Fig. 6, in which a part of the earth and 
its gaseous envelope is shown to scale. If 
the radius of the sphere is IZyi", then the 
non-conducting layer is only 1/64" thick 
and it will be obvious that the Hertzian 
rays cannot traverse so thin a crack be- 
tween two conducting surfaces for any 
considerable distance, without being ab- 
sorbed. The theory has been seriously ad- 
vanced that these radiations pass around 
the globe by successive reflections, but to 
show the absurdity of this suggestion refer- 
ence is made to Fig. 7 in which this process 
is diagrammatically indicated. Assuming 
that there is no refraction, the rays, as 
shown on the right, would travel along the 
sides of a polygon drawn around the solid, 
and inscribed into the conducting gaseous 
boundary in which case the length of the 
side would be about 400 miles. As one- 
half the circumference of the earth is ap- 
proximately 12,000 miles long there will be, 
roughly, thirty deviations. The efficiency 
of such a reflector cannot be more than 25 
per cent, so that if none of the energy of 
the transmitter were lost in other ways, the 
part recovered would be measured by the 
fraction (J4)^°. Let the transmitter radi- 
ate Hertz waves at the rate of 1,000 kilo- 
watts. Then about one hundred and fifteen 
billionth part of one watt is all that would 
be collected in a perfect receiver. In truth, 
the reflections would be much more nu- 
merous as shown on the left of the figure, 
and owing to this and other reasons, on 
which it is unnecessary to dwell, the amount 
recovered would be a vanishing quantity. 

Consider now the process taking place in 
the transmission by the instrumentalities 
and methods of my invention. For this 
purpose attention is called to Fig. 8, which 
gives an idea of the mode of propagation 
of the current waves and is largely self- 
explanatory. The drawing represents a 
solar eclipse with the shadow of the moon 
just touching the surface of the earth at a 
point where the transmitter is located. As 
the shadow moves downward it will spread 
over the earth's surface, first with infinite 
and then gradually diminishing velocity 
until at a distance of about 6,000 miles it 
will attain its true speed in space. From 
there on it will proceed with increasing 
velocity, reaching infinite value at the op- 
posite point of the globe. It hardly need 
be stated that this is merely an illustration 
and not an accurate representation in the 
astronomical sense. 

The exact law will be readily understood 
by reference to Fig. 9, in which a transmit- 
ting circuit is shown connected to earth and 
to an antenna. The transmitter being in 
action, two effects are produced : Hertz 
waves pass thru the air, and a current 
traverses the earth. The former propagate 
with the speed of light and their energy is 
unrecoverable in the circuit. The latter 
proceeds with the speed varying as the 
cosecant of the angle which a radius drawn 
from any point under consideration forms 



ELECTRICAL EXPERIMENTER 



733 



Increase Your Will Power 
In One Hour 

Author of This Article Tells How He Quickly Acquired a Dominating 
Will Power That Earns Him Between $50,000 and $70,000 a Year 



FOUR YEARS ago a man offered me a 
wonderful bargain. He was hard up for 
money and wanted to sell me some shares 
in a young, growing company for $1,000. Based 
on the earnings of the Company the stock of- 
fered me was easily worth $5,000 — in fact, the 
man who finally bought the shares sold them 
again in five months at a profit of $4,300. 

The reason I didn't buy the shares was that 
I could no more raise a thousand dollars than I 
could hop, skip, and jump across the Atlantic 
Ocean. A thousand dollars! And my income 
only twenty-five a week. 

The second chapter in my lite began a few months 
later, when another opportunity came to me. It re- 
quired an investment of ^20,000 during the first year. 
I raised the money easily, paid back every penny I bor- 
rowed, and had $30,000 left at the end of the first 
year! To date, in less than four years, my business 
has paid me a clear profit of over jSzoo.ooo and is now 
earning between S50.000 and $70,000 a year. Yet for 
twelve years before, the company had been losing 
money every year! 

The natural question for my reader to ask Is, "How 
could you borrow $20,000 to invest in a business which 
had previously been a failure, after being unable to 
borrow $1,000 for an investment that seemed secure?" 
It is a fair question. Andd the answer can be given in 
two little words— WILL POWER. 

When the first proposition came to me I passed it by 
simply because I didn't have the money and couldn't 
borrow it. I went from one friend to the next and all 
turned me down. Several refused to talk business with 
me at all. They all liked me personally, and they asked 
me about the kiddies, but when it came to money 
matters I hadn't a chance. I was scared slifT every 
time I talked to one of them. I pleaded with them, 
almost begged them. But everybody had their "money 
all tied up in other investments." It was an old ex- 
cuse, but I accepted it meekly. I called it hard luck. 
But I know today that it was nothing in the world 
except my lack of Will Power, or rather my weak Will 
Power, which kept me from getting what I wanted. 

When I heard that the man sold those shares at 
a profit of $4,300, it seemed that my sorrow could not 
be greater. That profit was just about what my salary 
amounted to for four years! But Instead of grieving 
over my "hard luck," I decided to find out why I was 
so easily beaten in everything I tried to accomplish. It 
must be that there was something vital that made the 
difference between success and failure. It wasn't lack 
of education, for many illiterate men become wealthy. 
What was this vital spark? What was this one thing 
which successful men had and which I did not have? 

I began to read 
books about psy- 
chology and mental 
power. But every- 
thing I read was too 
general. There was 
nothing definite • — 
nothing that told 
me what to do. 

After several 
months of discour- 
aging effort, I fi- 
nally encountered a 
book called "Power 
of Will." by Prof. 
Frank Channing 
Haddock. The very 
title came to me as 
a shock. When I 
opened the book I 
was amazed. I 
realized that will 
power was the vital 
spar k — t h e one 
thing that I lacked. 
And here in this 
book were the very 
rujes. lessons and 
exercises through 
which anyone could 
increase their will 
power. Eagerly I 
read page after 
page; including 
such articles as, 
The Law of Great 
Thinking; How to 
Develop Analytical 
Power; How to Con- 
centrate Perfectly: 
How to Guard 
Against Errors in 
Thought; How to 
Develop Fearless- 
ness; How to Ac- 
quire a Dominat- 
ing Personality. 



Partial List of 
Contents 

The Law of Great Thinking 

The Four Factors on which It 
depends. 

How to develop analytical power. 

How to think "ail around" any 
subject. 

How to throw the mind Into de- 
liberate, controlled, productive 
thinking. 

Detailed directions for Perfect 
Mind Concentration. 

How to aoQulrp the power of 
Consecutive Thinking. Rea- 
soning, Analysis. 

How to acquire tlie skill of Cre- 
ative Writing. 

How to Kuard against errors In 
Thought. 

How to drive from the mind all 
unwelcome thoughta. 

How to follow any line of thought 
with keen, concentrated Powers. 

How to develop Reasoning Power. 

How to handle the mind in Cre- 
ative Thinking. 

Tlie secret of Building Mind 
Power 

How the Will is made to act. 

How to test your Will. 

How a Strong Will is Master of 
Body. 

What creates Human Power. 

The Six Principles of Will 
Training. 

Dellniie Methods for developing 
Will. 

The NINETY-NINE METH- 
ODS for using Will Power in 
the Conduct of Life. 

Seven Prluclples of drill In 
Mental, Physical, Peraonal 
jwwer 

FIFTY-ONE MAXIMS for Ap- 
plied Power of Perception, 
Memory, Imatrlnatlon, 8elf- 
Analysia, Control. 

How to develop a strong, keen 
gaze. 

How to concentrate the eye up- 
on what is before you — object, 
person, printed page, work. 

These are only a few of the manu 
BUbjecta treated. 



An hour after I opened the book I felt like 
a new person. My sluggish will power was 
beginning to awaken. There was a new light 
in my eye, a new spring in my step, a new 
determination in my soul. I began to see, in 
my past, the many mistakes I had made, and 
I knew I would never make them again. 

I practiced some of the simple exercises. 
They were more fascinating than any game of 
cards or any sport. 

Then came an opportunity to acquire the business 
which had lost money for twelve years, and which I 
turned into a ^50,000 a year money maker. Instead of 
cringing before the moneyed people, I won them over 
by my sheer force of will. I would not be denied. 
And my every act and word since then has been the 
result of my training in will power. 

I am convinced that every man has within himself 
every essential quality of success except a strong will. 
Any man who doubts that statement need only ana- 
lyze the successful men he knows, and he will find 
himself their equal, or their superior, in' every way ex- 
cept in will power. Without a strong will, education 
counts for little, money counts for nothing, opportuni- 
ties are useless. 

I earnestly recommend Prof. Haddock's great work, 
"Power of Will," to those who feel that success is just 
out of reach — to those who lack that something which 
they cannot define, yet which holds them down to the 
grind of a small salary. 

Never before have business men and women needed 
this help so badly as in these trying times. Hundreds 
of real and imaginary obstacles confront us every day, 
and only those who are masters of themselves and who 
hold their heads up will succeed. "Power of Will" as 
never before is an absolute necessity — an investment 
in self-culture which no one can afford to deny himself. 

I am authorized to say that any reader who cares to 
examine "Power of Will" for five days may do so with- 
out sending any money in advance. If after one hour 
you do not feel that your will power has increased, and 
if after a week's reading you do not feel that this great 
book supplies that one faculty you need most to win 
success, return it and you will owe nothing. Otherwise 
send only S3, the small sura asked. 

Some few doubters will scoff at the idea of will power 
being the fountainhead of wealth, position and every- 
thing we are striving for, but the great mass of intel- 
ligent men and women will at least investigate for 
themselves by sending for the book at the publisher's 
risk. I am' sure that any book that has done for me — - 
and for thousands of others — what "Power of Will" 
has done — is well worth investigating. It is interesting 
to note that among the 250,000 owners of "Power of 
Will" are such prominent men as Supreme Court 
Justice Parker; Wu Ting Fang, Ex-U. S. Chinese Am- 
bassador ; Gov. McKelvie, of Nebraska ; Assistant 
Potmaster-General Britt; General Manager Christe- 
son, of Wells-Fareo Express Co.; E. St. Elmo Lewis; 
Senator Arthur Capper of Kansas and thousands of 
others. In fact, today "Power of Will" is just as im- 
portant, and as necessary to a man's or woman's equip- 
ment for success, as a dictionary. To try to succeed 
without Power of Will is like trying to do business with- 
out a telephone. 

As your first step in will training, I suggest im- 
mediate action in this matter before you. It is not 
even necessary to write a letter. Use the form below, 
if you prefer, addressing it to the Pelton Publishing 
Company. 30-B Wilcox Block, Meriden, Conn., and the 
book will come by return mail. You hold in your hand, 
this very minute, the beginning of a new era in your 
life. Over a million dollars has been paid for "Power 
of Will" by people who sent for it on free examination. 
Can you, in justice to yourself, hesitate about sending 
in the coupon? Can you doubt, blindly, when you can 
see. without a penny deposit, this wonder-book that 
will increase your will power in one hour. 

The cost of paper, printing and binding has almost 
doubled during the past three years, in spite of which 
"Power of Will" has not been increased in price. The 
publisher feels that so great a work should be kept as 
low-priced as possible, but in view of the enormous in- 
crease in the cost of every manufacturing item, the 
present edition will be the last sold at the present 
price. The next edition will cost more. I urge you to 
send in the coupon now. 



PELTON PUBLISHING COMPANY 

30-B Wilcox Block, Meridenr Conn. 

I will eiamine a copy of "Power of Will." at your risk 
I agree to remit $3 or remaU book In 5 days. 



Name. . . 
Address. 
City 



You benefit by mentioning the "Electrical Experimenter" when writing to advertiv^rt 



734 



ELECTRICAL EXPERIMENTER 



1 



H.P.,11Qvolts,A.C. 
60 cycle, single 
phase,] 750 R.P.M. 




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Bought from Bankruptcy Stock 

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MANUFACTURERS' OlSTfllBUTEfl 



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Merchant Marine Needs THOUSANDS of Operators 

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graph companies. Salaries up to $200 a month. E.'.cellent opportunities to win promotion 

to Kadio Engineer— Inspector — or Draftsman. Chance to travel the world 

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Complete Course by Mail in Ten Weeks 

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Btart gtudjlni! NOW In spare time at home. We send you Complete Set 
JTactlco Instruments for receiving and sending mes.sa«es, with first lessons. We 
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Service. Write TODAY for Free Particulars. A postal will do 



NATIONAL RADIO INSTITUTE 
Dept. 68 Washington, D. C. 




Grinding and Buffing Motors 

An indispensable tool in any shop or laboratory. Your equipment is not 
complete without a BODIXE grinding and buffing motor. 
Save time and money by keeping your lathe tools, milling cutters and 
drills sharp. 

Send for bulletin No. 522 giving fill! details of this handy machine. 
BODINE ELECTRIC COMPANY. 2254 W. Ohio St.. Chicago. 



February, 1919 

with the axis of symmetry of the waves. 
-\t the origin the speed is infinite but grad- 
ually diminishes until a quadrant is 
traversed, when the velocity is that of light. 
From there on it again increases, becoming 
infinite at the antipole. Theoretically the 
energy of this current is recoverable in its 
entirety, in properly attuned receivers. 

Some experts, whom I have credited with 
better knowledge,' have for years contended 
that my proposals to transmit power with- 
out wires are sheer nonsense but I note 
that they are growing more cautious every 
day. The latest objection to my system is 
found in the cheapness of gasoline. These 
men labor under the impression that the 
energy flows in all directions and that, 
therefore, only a minute amount can be re- 
covered in any individual receiver. But 
this is far from being so. The power is 
conveyed in only one direction, from the 
transmitter to the receiver, and none of it 
is lost elsewhere. It is perfectly practicable 
to recover at any point of the globe energy 
enough for driving an airplane, or a pleas- 
ure boat or for lighting a dwelling. I am 
especially sanguine in regard to the lighting 
of isolated places and believe that a more 
economical and convenient method can 
hardly be devised. The future will show 
whether my foresight is as accurate now as 
it has proved heretofore. 



SHIP RADIO OPERATORS ASK 
INCREASED WAGES. 

Increased wages and the fixing of a 
standard wage scale for radio operators on 
vessels operating under Government direc- 
tion was asked of the Shipping Board re- 
cently by a delegation representing the Mar- 
coni Radio Telegraphers' Association. The 
radio operators included in the request made 
of the Board are those on vessels operat- 
ing in transatlantic and Gulf waters. As- 
surances were given the radio representa- 
tives by Board officials that their request 
would be taken under advisement for im- 
mediate consideration. 



TRATTSIvIITTEK^ IBXJTTOrTi 




THE S K I N • 
DER VI KEN 
TRANS- 
MITTER BUTTON 
presents the lateut 
advance In micro- 
phones and marks 
a revolution In 
transmitter c o n - 
structlon. It works 
on an entirely new 
principle, takes up 
p racticaUy no 
room, and marks 
the end of all telephone transmitter troubles. 

The 8KIN0ERVIKEN TRANSMITTER BUTTON can be placed In any 
position and It will talk loudly and distinctly and Is at the same 
time extraordinarily sensitive. It was primarily designed to replace 
the old damaged or burnt out transmitter. Simply unscrew and 
remove the telephone transmitter front, disconnect the two inside 
wires, unscrew and remove the bridge and the old electrode. 
There remains only the diafram. These wires are then connected 
with the Sklndervlken button, the latter screwed to the diafram, 
and after screwing the old transmitter bousing together again, 
the telephone ts ready for work. 

ELECTRICAL EXPERIMENTER readers wUl be particularly 
Interested in all the diiTerent experiments that can be performed 
with the Skinderviken Button. Fig. 1 shows tiie Skindervlken 
button attached to the back of an Ingersol watch case. When 
speaking towards the inside of the case, it will be found that the 

voice la reproduced 
clearly and loudly 
Fig. 2 shows an- 
other Interesting 
stunt. By attaching 
the button to a tin 
diafram about the 
size of half a dol- 
lar, and by holding 
the diafram at the 
side of the throat, 
as shown, speech 
can be transmitted 






with surprising 
clarity. Fig. 3 il- 
lustrates the same 
arrangement placed 
on the chest as 
shown. In this po- 
sition the trans- 
mitter will talk 
clearly and loudly. 
Fig. 4 shows an ar- 
rangement whereby 
the SklnderFtken 
button is atta-'*hed 
on a tbln wood 
board at the preacher's pulpit. His voice Is clearly transmitted so that 
people hard of he:; ii g can readily hear the sermon. Fig. 5 shows an In- 
teresting stint, whereby a hole Is drilled in the side of a thin 
class water-tumbler; the sides of the glass thus acting as a dia- 
fram, the voice Is clearly transmitted. Fig. 6 shows a simple 
match box Detectophone. The Skinderviken button is concealed 
inside of the box, only the small brass nut showing on the out 
side. This can be camouflaged as well. This device talks well. 
Fig. 7 shows how to transmit phonograph music at a distance 
merely by drilling a small hole in the phonograph arm and at- 
tarhlng the Skinderviken button ; a very favorite experiment with 
all e.trerlmeritprs. PI*. 8 showa how a very §en8lt!ve Detectophone can be 
made by placing one of the buttons In Uie center of a Htho«raphed card- 
Iward picture, so that only the sinall brass nut Hhows. The lame Burface 
of the picture acts as a big diafram. and the voire ia well reproduced. 

We have such unlimited confidence In the Skinderviken transmitter but* 

Ion that we make the following remarkable offer. Send us one dollar 

($1.00) for which we 

will mall one button PHONOGRAPH >\ A3 A" 

MUSIC AT A /^ X DETeaOPHONd 

PI stance/ /\ ONPiauRE 



prepaid. If you do 
not wish to keep It, 
return It within Ave 



days nnd your money 
will be refunded. 
Boys! send stamp for 
booklet No. 4. It 
gives diagrams and 
experiments using the 
Skinderviken Trans- 
mitter Button, and 
prices of telephone 
equipment. 




r.,.7 




SKINDERVIKEN TELEPHONE EQUIPMENT CO. Address us as STECO, 2134 N. Clark St., Chicago, III 




February, 1919 

ALEXANDER WIRELESS BILL, 
AMENDED. 

(Continued from page 707) 



ELECTRICAL EXPERIMENTER 



735 



"Seventh. It shall be 
lawful for the Govern- 
ment to deputize own- 
ers of private or ama- 
teur stations at a nomi* 
nal fee for the purpose 
of having the radio 
rules and regulations 
enforced in such locali- 
ties as the number of 
stations so warrants 
such a proceeding. 



"Eighth. The Gov- 
ernment shall have the 
right to permanently 
revoke any license held 
by a private or amateur 
station as an extreme 
penalty for disobeyance 
of the radio rules and 
regulations set forth hy 
this Act and any previ- 
ous Acts concerning 
radio telegraphy. 

"Ninth. It shall be 
lawful for the Govern- 
ment to provide tech- 
nical schools and State 
universities with radio 
stations for the benefit 
of science and the 
training of radio oper- 
ators. 

"Tenth. It shall be 
lawful for the Govern- 
ment to require all pri- 
vate or amateur sta- 
tions to use inductive 
coupling between the 
antenna circuit and the 
circuit which includes 
the power transformer 
for damped radiotele- 
graphic communication. 

"Eleventh. It shall 
be unlawful for any 
private or amateur sta- 
tion to use a spark coil 
operating on direct cur- 
rent for the sending of 
radio disturbances into 
the ether. 



"Twelfth. It shall be 
unlawful, except by 
special license, for any 
private or amateur sta- 
tion to use more than 
one hundred and 
twenty-five watts as 
measured in the an- 
tenna circuit, for the 
sending of radiotele- 
phonic communications. 



"Thirt e enth. The 
Government shall have 
the right to suspend 
the sending of radio 
disturbances into the 
ether by private or 
amateur stations for 
definite periods of the 
night or day in such 
zones as may become 
necessary, but nothing 
in this article shall be 
construed to mean that 



No fundamental ob- 
jection to this phase. 
It was already done in 
a silent way by tacit 
agreement among the 
amateurs before the 
war. It was very com- 
mon for the Editor of 
this as well as other 

fiublications to receive 
etters from amateurs 
complaining of fellow 
amateurs who had in- 
fracted the law. A let- 
ter to such violators 
from the various pub- 
lications devoted to 
wireless usually brought 
speedy redress. Ap- 
parently no law was 
necessary. 

We have no objec- 
tion against this either. 
An amateur should 
have his license re- 
voked if he does not 
play the game fair. In 
the five years that the 
1912 Radio Act was in 
effect, however, we 
have not heard of a 
single case where a 
license was revoked. 

No objection to this. 



No objection. 



We fail to see the 
wisdom of this. An 
amateur with a spark 
coil, we admit, can 
cause a lot of disturb- 
ance, but it should be 
remembered that a Gov- 
ernment or commercial 
station can readily tune 
out such an amateur 
station without any 
trouble whatsoever 
even if it operates a 
block away. Further- 
more, if no spark coils 
could be used, the ama- 
teur would natural! 
resort to a transformer, 
and there is no such 
apparatus made today 
which uses less than 
100 watts. Most of 
the spark coils use less 
than 30 or 40 watts, 
consequently send out 
less disturbance than 
would be the case un- 
der the new measure. 

We believe that 125 
watts is not sufficient. 
In a few years there 
will be thousands of 
radio telephone stations 
operating all over the 
country, and they will 
be as common as the 
telephone is today. 
Ours is a country of 
vast distances. This 
law would work espe- 
cial harm to our west- 
ern states where there 
are often no settle- 
ments a hundred miles 
apart. One hundred 
and twenty-five watts 
as measured in the an- 
tenna circuit we believe 
is insufficient to bridge 
such distances. We be- 
lieve 250 watts should 
be the minimum. 

Yes, every bill must 
have its usual joker, 
and it is right here. If 
this clause becomes a 
law then any officious 
Government operator 
can take it into his head 
to prohibit sending in 
his district between the 
hours of 4 P. M. and 
12 A. M. This period 
would be considered 
night. You said it. 



the sending of private 
or amateur stations 
shall be permanently 
suspended. 



"Fourteenth. The 
owner of the license of 
any private or amateur 
station must display in 
h is station a copy of 
the rules and regula- 
tions of the Govern- 
ment regarding radio 
stations and failure to 
do so shall be punish- 
able bjj a fine not ex- 
c e e d i n g $100, such 
rules and regulations 
to be furnished by the 
Government at a nomi- 
nal cost." 



"GOOD Night" It 
would, of course, blot 
out all the sending sta- 
tions with one stroke. 
If we must have a time 
limit, let it be stated 
in the law so there will 
not be any "ifs" and 
"buts" — at best such a 
clause as this would 
tend to create eternal 
friction between ama- 
teurs and Government 
officials. We believe 
such a clause is unjust 
and only at best reflects 
on poor and inadequate 
Government apparatus 
and still more inefficient 
Government radio oper- 
ators. 

No objection to this, 
altho every amateur 
operator before the war 
was only too proud to 
display his Government 
license once he had 
gone thru the trouble 
to get one. 



RADIO AMATEURS DISGUST 
OFFICIALLY. 

During the hearings of the Alexander 
Bill, H. R. 13159, before the committee on 
the Merchant Marine and Fisheries on De- 
cember 12, 1918, many interesting points 
were brought out. 

Lieut. J. C. Cooper, Jr.,.U. S. N. R. F.. 
had been intrusted with drafting the ama- 
teur amendment, printed elsewhere in this 
issue. Lieutenant Cooper, who calls him- 
self an "amateur naval ofificer", undertook 
the thankless job of drafting an amend- 
ment which would satisfy both the Navy 
and amateurs. In fairness to Lieutenant 
Cooper, let us state that he tried hard to be 
fair to both interests. But it is our opinion 
that neither Navy Department nor Ama- 
teurs are fully satisfied with the comprom- 
ise amendment. 

Lieutenant Cooper's statement before the 
committee follows: 

Statement of Lieut. J, C. Cooper, Jr., United 
States Naval Reserve Force. 

Lieut. Cooper: Gentlemen, I am an ex-amateur 
radio operator and **amateur naval officer," as I 
am soon going back to civil life to take up the 
practise of my profession again. As many other 
amateurs, when the war broke out, I offered to do 
what I could for the service, and have had some 
duties in connection with radio work which have 
given me an opportunity, I hope, to be able to see 
the point of view of the Navy and the point of 
view of the amateur operator to some extent at the 
same time. 

Several days ago there was a meeting called in 
Capt. Todd's office — without knowing now many 
men would be present — of all_ of the ex-amateurs 
who happened to be on duty in the naval service 
in Washington. There were about 25 or 30 men 
present. The question of the operation of amateur 
stations after the war was very liberally discust, 
and a memorandum was prepared and sent to each 
of those men and other men in the naval ser- 
vice in Washington who had been amateurs that 
we could locate, with the request that the questions 
be answered and sent back as soon as possible, 
with an idea of drafting an amendment to the pres- 
ent law which would, as far as possible, meet the 
combined view of themselves as previous amateurs, 
knowing amateur operations and knowing what the 
amateur desires to do and what he has done, and 
also with their experience since the war as part 
of the Government's service that has controlled 
radio. I had the unfortunate responsibility of hav- 
ing to say the final word on collating those opin- 
ions and putting them into the form of an amend- 
ment. There is no body of men, I believe, who 
disagree more violently among themselves on every 
subject that concerns them than do the amateur 
radio operators. I am convinced that from now 
on, as these hearings are going to be printed, my 
name is going down in radio history among the 
amateurs to some as guilty of high treason, to 
others as being foolish, to others as deserving some 
credit if this amendment goes into lew. I do not 
expect all the amateurs to agree witti it all. It 
is the collective judgment, however, of a certain 
number of amateurs who have seen both the Navy 

Joint of view and the amateur point of view, and 
, myself, with the approval of the department, and 
it is offered as an amendment to the bill. 

The present law states that the amateur who does 

not hold a special license is authorized within 5 

miles of a Government station to use a transformer 

input of one-half kilowatt, elsewhere 1 kilowatt, 

(Continued on page 737) 



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ELECTRICAL EXPERIMENTER 



737 



RADIO AMATEURS DISGUST 
OFFICIALLY. 

iCont.niicd from page 735) 

and to use a maximum wave length of 200 meters. 
AH amateurs are agreed that you can not properly 
tune an efficient amateur station quite as low as 
200 meters ; that an extension in \\ ave length is 
desirable. The consensus of opinion of those I 
have talked to is that the limitations of this amend- 
ment — that is, not to exceed 250 meters — will great- 
ly increase the efficiency of amateur stations and 
will enable the amateur to further fulfill his real 
function, winch is to train him as an operator for 
any national emergency that may arise, and to pos- 
sibly train him as a further developer of the radio 
art. The amateur has no place in the scheme of 
things if he is not useful. The ether is a means 
of communication which must be put to the use of 
the community as a whole for the advancement of 
the community. Unless the amateur operator ad- 
vances the art, or advances the community, the ama- 
teur has no right to exist. I, personally, as a naval 
officer, have had many operators under me. I have 
found that of the new men under me the easiest 
trained, the most adaptable to the new apparatus, 
and the most efficient men I had were ex-amateur 
operators. 

I took two of my best men the other day and 
put them on the President's ship to receive offi- 
cial messages from Washington. They were both 
ex-amateur operators; and 1 think that I speak 
for Capt. Todd and the Navy when I say that no 
one more than the Navy realizes the value that the 
amateur operator was to the Navy when the war 
first broke out. I, personally, of course am preju- 
diced in favor of the amateur, becaust I am prais- 
ing myself when I praise the amateur, because I 
am an amateur operator. 

This amendment also licenses receiving stations 
without requiring a license of the operator. In 
other words, the jeweler who has a receiving sta- 
tion simply for the purpose of receiving the Arling 
ton time signals and cnecking up his chronometer 
will not require to be a radio operator to operate 
his receiving station. Likewise, the amateur who 
is only learning to send, who is just starting, will 
not have to have any license in order to operate 
a receiving station.* We do not think, on the 
other hand, that any amateur ought to have a 
right to touch the key and to cause possible blun- 
dering interference by his lack of ability as an 
operator unless he can receive and send what is 
usually called 1 5 words per minute ; that is, 75 
letters per minute, in the ordinary standard of 5 
letters to the word, which is what we use in aver- 
aging an operator's speed. I personally do not 
think that that limit is too high. Others may dis- 
agree with me. I personally think that no operator 
ought to touch a key and ought to be allowed to 
interefere with this medium of commerce, which is 
the ether, unless he has that degree of skill. If 
he is required to have that degree of skill, it will 
be an incentive to him when he is first learning the 
art to get up to that degree of skill as soon as he 
can, so that he can have a transmitting license. 

This amendment includes a clause authorizing 
the Government, where it is found expedient — as, 
for instance, in large centers or elsewhere — to limit 
the transformer input of amateur stations to one- 
half kilowatt if within 100 miles of the seacoast 
or within 5 miles of a Government receiving sta- 
tion to one-fourth kilowatt. I am frank to say 
that those powers are higher than the consensus 
of opinion of these written documents from which 
I compiled the amendment. Those powers are more 
liberal than the great majority ot the men who 
compiled these memorandums thought proper, but 
after talking with Capt. Todd and Commander 
Hooper, and with especially this idea in view, 
namely, that there are many amateur stations which 
will have to apply for license before they can again 
reopen, who, if the input is cut down very much 
from the present law, will be required to remodel 
a part of their apparatus or give up their appara- 
tus if we change the power limits very much. Per- 
sonally, I think that those limits are as reasonable 
as can be safe from the point of view of non- 
interference with the real business of radio, which 
is sending official and commercial dispatches, and 
that those powers are ample to provide full ex- 
perimentation that an amateur ought to have occa- 
sion to do and all communication that he may have 
occasion to make. Mark me, it does not say that 
a license can not be issued up to 1 kilowatt under 
those limitations. It says that the Government may 
in its discretion put those limits on. 

For example, we will take on the peninsula of 
Michigan or on parts of the more or less unin- 
habited coasts of the Gulf, there is no reason why 
there would be stations near enough or ships work- 
ing near enough so that I kilowatt would neces- 
sarily cause interference by what we call "forced 
oscillation." The amendment leaves it in the dis- 
cretion of the licensing power to cut down to those 
limitations amateur stations which are near the cen- 
ters of commerce, where other stations are using 
radio for its real purpose, and still it allows the 
amateur to work. 

There are a lot of amateur operators here, some 
of whom I have known personally; some I have 
met since I have been here to-day; some I have 
had correspondence with before the war. A lot of 
them are going to disagree with me; some of them 
are going to think these limitations too low and 
some are going to think these limitations too high. 
That win be for the committee to decide. This is 
submitted by the Navy as a measure to assist in the 
future development of amateur radio. 



K. I. Shorthand hastened his promotion from 

stenographer to executive; now he depends upon 

it more than ever 



*The amendment, printed elsewhere, fails 
show this. — Editor. 

(Continued on page 738) 



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Mr. Saunders: I want to ask you a few quci- 
tions about the amateur. You have read the bill 
that is under consideration by the committee? 

Lieut. Cooper: I have read it, sir. 

Mr. Saunders: Aside from your amendment you 
have been discussing, there is no provision in the 
bill whatever relating to amateurs, is there? 

Lieut. Cooper: I understand, sir, it was the in- 
tention of the department to license amateur opera- 
tors. 

Mr. Saunders: Under the bill that has been 
introduced there is no provision for the amateur? 

Lieut. Cooper: Not under the name "amateur." 

Mr. Saunders; Is there under any other name? 

Lieut. Cooper: I think, sir, there would have 
been no reason why amateur stations should not 
have been licensed under the term "experimental 
stations." 

Mr. Saunders; Suppose it is just a single in- 
dividual. I understand a great many of these peo- 
ple who are amateurs took up this thing before the 
war — just young men who took up the businesi 
themselves? 

Lieut. Cooper: I did so myself. 

Mr. Saunders; That would not be called a sta- 
tion, would it? 

Lieut. Cooper; Oh, yes, sir. 

Mr. Saunders; Do you think, under the language 
"experimental stations," that any little individual 
amateur operator in the wilds of my district. I will 
say, who has been working on the thing himself 
as an intellectual improvement, could be described 
as "experimental station"? 

Lieut. Cooper: I think so. But I say it is a 
moot point in view ot the amendment. 

Mr. Saunders; I do not see how that could be 
done with respect to the provision as to who ia 
to be licensed as an amateur. Under that, neces- 
sarily, before any man could start out as an ama- 
teur, he must have had the opportunity to take 
some training at some school. 

Lieut. Cooper: Very frankly I think that very 
few amateurs ever went to a training school. 

Mr. Saunders; You require them to possess cer- 
tain capacities by your amendment; they have got 
to have a certain facility. 

Lieut. Cooper: The amateur can learn that by 
using the buzzer. All amateurs do the same thing, 
all operators. 

Mr. Saunders: Can he experiment enough with 
the wireless apparatus to acquire that facility with- 
out having a trainer? 

Lieut. Cooper; May I suggest, sir, that the 

firocess would be something like this: That by 
istening in, as we call it — and you will note that 
no license is required for receiving — a man can 
become accustomed to using the receiving appara- 
tus, and he can become accustomed to the sending 
with a key hitched to a little buzzer, which is not 
a radio operator, and he can be taught to send 
up to any speed he can ever attain. 

Mr. Saunders: He can teach himself, in other 
words, can he? 

Lieut. Cooper: Teach himself, or be taught by 
other amateurs. 

Mr, Saunders; Hr can pick that up by his own 
efforts, and by his own ingenuity and application 
at home and can acquire the facility which you 
have imposed upon him before he can receive a 
license? 

Lieut. Cooper: I think any of the amateurs here 
will agree with me on that. 

Mr. Saunders; With respect to this amateur, 
after he has attained that speed, and then is given 
the license that you contemplate, all of his opera- 
tions would be controlled by the terms of his 
license? 

Lieut. Cooper; They are at present, under the 
present law. 

Mr. Saunders: Do you contemplate any diffi- 
culty in that connection if he operates according 
to the terms of his license, with the commercid 
operation of the Government system, or any other 
commercial system ? 

Lieut. Cooper: The limitation of wave lengths, 
sir, and the limitations of power in the present 
law of 1912, as amended by this amendment, are 
designed to prevent the amateur from causing in- 
terference with commercial stations. 

Mr. Saunders; But you can see no danger of in- 
terference with the wireless system in the hands 
of private enterprise or Government control? 

Lieut. Cooper; It was my view, sir, in drafting 
the amendment as it is, that these limitations on 
power and wave lengths would prevent such inter- 
ference. 

Mr. Saunders: So that in considering the general 
problem with respect to the necessity of having 
this entire business under Government ownership 
and control, we can eliminate any factor of danger 
from amateur operators? 

Lieut. Cooper: I think so, sir, with the excep- 
tion of the fact that adequate inspection of amateur 
stations must be had in the future if the amateur 
is to maintain the dignified position in the radio 
world that he should. 

Mr. Saunders: That is by regulation? 

Lieut. Cooper: Yes, sir. 

Mr. Saunders: As I said, you eliminate^ the 
amateur experimentors as a factor in determining 
this policy, because they will operate in a field out- 
side of the field that this policy is designed to con- 
trol? 

Lieut, Cooper; That is the idea of the amendment. 
There is one coming factor in radio work which 
may adversely affect amateur operating which 
should be looked forward to at the present time. 
The fleet — and this is not disclosing military secrets 
— is using for intercommunicating purposes very 
short wave length, shorter than tne one hundred 
fifty meters mentioned here as the minimum len^h 
that an amateur should use. Aircraft are also using 
various wave lengths, some of which are almost 
(.Continued on Page 742) 



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February. 1919 



ELECTRICAL EXPERIMENTER 



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ELECTRICAL EXPERIMENTER 



February, 1919 



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February, 1919 



ELECTRICAL EXPERIMENTER 





Edited by H. GERNSBACK 



Combination Carriage and Sled. 

(299) Peter E. Sparri, Detroit, Mich., sends us 
a description ot a combination foot-power carriage 
and sled. This apparatus works by means of a 
paddle that can be raised or lowered at will. When 
converting the sled into a carriage, the runners 
are taken off, the back wheels are placed on the 
paddle axles and are pulled down and locked. 

A. This idea is very unique and should find 
favor particularly in our northern states where 
there is a good deal of snow. We think a patent 
might be obtained on this device. 

The same inventor also submits what he terms a 
"desk telephone," which is to do away with hanging 
up and taking down of the receiver. The idea is 
to have a stand which when lifted up makes the 
connections, while the entire combination is similar 
to the hand telephones, which incorporate a re- 
ceiver and microphone combined. 

A. This is a good idea, but we cannot offer 
much encouragement as to the patent phase, for 
the reason that a great many such devices are on 
the market and hundreds more have actually been 
patented. Somehow or other, there does not seem 
to be a very widespread demand for this apparatus. 

Diving Device. 

(300) Jess F. Perrin, Rapid City, S. D., writes 
as follows: "I have two ideas on which I would 
like to have your opinion as to practicability, use- 
fulness and demand on the market. The first one 
is a small rubber device which fits in the nostrils 
to exclude the water when diving. It is thought 
that a device of this kind would be of great service 
to amateurs in learning how to swim. It could be 
retailed at 10c." 

.^.Without seeing the details and construction 
of this device, it is impossible for us to say 
whether it has any merit. We think, however, 
that there might be a demand for a device of this 
kind. 

"The other device is an automatic printer for 
printing pictures. An automatic counter keeps the 
operator apprised as to the number of prints being 
taken. The prints are run thru all the necessary 
solutions and run out on a belt to dry. This 
™^'^5!,'J>'^Aj°"y, ''^ '"^<^^ *' ="" expense not exceed- 
ing $20.nn Your advice on this would also be ap- 
preciated. ^ 
A. There does not seem to be anything funda- 
mentally new to this idea, and there are several 
printing machines of this kind on the market at 
the present time. 

Automatic Airplane Control Stabilizer. 

'^"'^ ..-^'^'"^"^ '*■ ^'ofng. Covington, Ky 
writes: Most airplanes are controlled by a 'joy- 
stick, a lever on a universal joint arranged so that 
by moving it from side to side the airplane is 
steered and by moving backward and forward the 
elevation is changed. My idea embraces two levers 
one to move forward and backward and the other 
to move from side to side. At the top of each 
of these levers, which are connected to the regular 
control wires just like a double control 'plane, is an 
iron rod. At the ends of these iron rods are mag- 
nets so that when the magnet at either end is ex- 
cited It draws the iron rod, and joystick, a few 
inches in that direction, thus controlhng the 'plane 
Another magnet when excited will draw the rod 
still farther. The same applies to the other end 
of the iron rod and the other "joystick." 

The principal part is the means for telling when 
these magnets should be excited. Just as we have 
tubes in our heads to tell us when we are off 
balance (literally) so is this apparatus intended 
to tell the airplane when it's off balance. A closed 
tube, longer than it is wide to prevent electrolyte 
from splashing, is fitted with a main contact in the 



bottom and contacts at each end so that if the 
plane dips forward (for example) the electrolyte 

exci'tel°7rt[''' "'''^" "'S^l' "''>' '"<= first eontact! 
excites first magnet and by the magnet drawing 
the joystick'' forward the level of the 'plane ii 
corrected. If the 'plane continues to dip, the 
sS" f"'^^"'!,' '^,^\'--i'^d which draws the "joy! 
small magnets may be used so as to affect the 

nnlv ^' ^ °^^r ; Jo.ystick" fitted the same way 
only crosswise of the 'plane warps the wings or 
rnoves the aerofoils (at ends of w^ngs) t" Tontrol 
on'a'^leve'l'."" """ '"'^""^ ='"'' ^^'^ '^^ two wings 
r,,,!"?,^ "''/''■5" ""■' i' "^ti^ of porcelain, with a 

Thidc nilv e>l^,"r. "•; '"^''^^ '" P'-'=^™' 'he rathe? 
thick oily electrolyte from mov ng too freelv has 

facTs"?a,'°^'/" ^° "'^'^-"jO- an^d the other' con 
tacts (as many in each end as there are magnets 
tube Tv"''- "f , -""yitick") at each end of^ the 

^l^not^ll-v^y.-aLVth'rwh-otnpVTati^^d^eTn:? 

c1,tg7sTn^tt™a°"pfanl<^°" "°' '^■' *" -'-=^= 

When the aviator changes the level of the 'plane 

that when^^h*" """i '"'^' °' ""= porcelain tufeso 
that when the airplane gets off of that level the 
device automatically corrects the position Thl 
position of the magnets change when the aviator 

wh'eTthe*^,- 'r^' "f 'he porfelain tubes so ?ha 
when the airplane is on the correct level the ma^ 
nets are at the ends of the iron rods at the Tops 
of the "joysticks" ready for business. The aviator 

c^:i!^i^?\^^ frti?ir"e''^^^' ^"^ '"'^ ^'-p-'- 

Ypjng ^rer;L='mSif'c''reilt«?orhl'fn^^e„tTo?t ^As 

wil be noted Mr. Young has tried ?o3es°gn an 

electro-mechanical brain^ for the airplane ^ It is 

this kindTo k "' "^" ''""='" ^"'" has a device o 
tnis kind to keep us in an upr ght position Fin^ 

■^^11 '"""' ? '''J"''' ™hich runs back and forward 
m these tubes and we thus stabilize ourseTves 

^ulZ^an "'.,"■',"' i'" "^''^ "^e °f 'his prfncTple 
oy using an electrolyte m a closed vessel pViH 

ceruif controf' """°"^ 'T'^'' ^° ^= To energTze 
abo" magnets, substantially as set forth 

tr.^^!}^ '■''^ '"l^^ '^ 8°0<i- we have only one fault 
to find, VIZ., that the vessel containing e?ectroWte 

S IS^Hn^-H? -™-S 
ronf,rf= ., ■ k "" he readily imagined. If the 
contacts can be arranged in relatively fine, long 



In this Department we publish such matter as is of interest to invonf^.-. —j T \ I 

those who are in doubt as to certain Patent Phases. Regular inquiries addrest to ^•P»t'',nri^;''^ 'S 
cannot be answered by mail free of charge. Such inquiries are nuh (.Thf I,™ V .uu* c'*''\'". 
readers. H the idea is thought to be of importance, we make ?t a rule no^ to^'fju el airde,'.^' "" 
order to protect the inventor as far as it is possible to do so divulge all details, in 

Should advice be desired by mail a nominal charge of $1.00 is made for each o..>,.ti„„ ei, . u 
and descriptions must be clear and explicit. Only one side of she^t should be'^ wr^Uen on. ^''^"''" 

Readers' attention is called to the fact that 
due to the great amount of letters to this de- 
partment it is quite impossible to answer them 
all thru these columns: The inquiries answered 
in this issue date as far back as August, and if 
readers wish speedy service they should care- 
fully note the announcement appearing in the 
preceding paragraph. 



U.S. 



741 

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742 



TO THE MAN 
WITH AN IDEA 

I offer a coraprehensivc. ex- 
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ELECTRICAL EXPERIMENTER 

tubes where a displacement of the liquid will take 
place gradually, we believe that the device will 
tunction with a greater degree of success. 

Automatic Air Hose Coupling. 

(302) James Witkowski, .\lbioii. X. Y., submits 
a drawing of an automatic air hose coupling with 
drawing, and wishes our opinion whether it is 
patentable and if it would be of anv value if a 
patent could be obtained on it. 

A. It is impossible to figure out on paper 
whether the brake would work satisfactorily. In- 
deed, we are not sure that the device is at all 
new. We would advise our correspondent to have 
a search made in the patent office thru one of the 
p.itent attorneys to ascertain what has been done 
previously in the art. 

Electric Heater. 

(303) Gottlieb Samuel Leventhal, Elmira, N. 
1., submits a drawing on an electrical idea for 
heating water. The device is of the usual type 
whereby it can be attached to any faucet, the water 
started running and the current turned on. As 
the water runs thru this device and over the heat- 
ing wires, the water is heated. 

A. There is nothing fundamentally new to the 
device as submitted, except for the attractive form 
that our correspondent has given it, which is in 
the shape of a round ball. Outside of this, there 
is nothing new shown, and we are quite certain 
that no patent could be obtained. 

Mechanical Brake. 

(304) Emilio R. Salazar, Havana, Cuba, writes 
as follows: "I am enclosing blue-print and de- 
scription of a contrivance to appiv brakes on rail- 
road cars with a request for you to publish it with 
your advice on the idea in your Patent Advice 
Section. Will you kindly let me know the possi- 
bilities of this invention?" 

A. This is quite a complicated apparatus, and 
without seeing a model we think it is almost 
impossible for anyone to give an intelligent opin- 
ion. A brake of this kind looks all right on paper, 
but iL IS difficult to predict in advance if it will 
work out in practise. We would earnestly advise 
that before applying for patent on this apparatus 
that a model should be built 



February, 1919 



BOY BURNED WHEN WET KITE 
STRING TOUCHES WIRES. 

While Wm. Oliver of Port Stanley was 
amusing hunself recently flying his kite he 
was severely burnt on both hands, when the 
flying string came in contact with the 
high voltage wires of a local railway. 
While flying his kite a strong wind sent it 
to the ground, and the wet cord came in 
contact with this power wire, as it fell over 
it. The victim got the full benefit of the 
voltage. This was much too strong for the 
string as it burnt it in two, for which Wil- 
liam is very thankful as it saved his life. 
The only other small boy there ran away 
when he saw what had happened so he was 
alone when all was over. The burnt hands 
healed up all right, but Master Oliver, for 
one, will keep clear of all overhead electric 
wires hereafter, when he goes kite flying. 
It IS remarkable that he was not killed out- 
right, the high resistance of the kite string 
probably being the factor that saved his life. 



RADIO AMATEURS DISGUST 
OFFICIALLY. 

(Continued from page 738) 

down to 250 meters. There nray be trouble in the 
future, sir, between aircraft operating overland 
and working with their receiving or transmitting 
stations, and amateur stations. That is a possi- 
bility of the future that I will call the attention 
of the committee to at this time, because this thing 
may come up here at another time under some 
future law, and, I simply want to warn the com- 
mittee that this is a new field that we know nothing 
about. Aircraft radio was not in existence to any 
extent when amateurs last operated. There may 
be interference between amateur operators and air- 
craft radio stations, but it is hoped that there will 
not be. 

Mr. Saunders: Government ownership has noth- 
ing to do with that problem? 

Lieut. Cooper: Except the Government would 
probablv be operating the stations for aircraft. 

Mr. Saunders: The possibility which you speak 
of which may arise hereafter is a thing that will 
be met by appropriate regulations, is it not? 

Lieut. Cooper: It might be, sir, if this amend- 
ment is past, that it might have to be met by legis- 
lation again reducing the wave length back to 
where it is now. 

Mr. Saunders: Appropriate legislation? 

Lieut. Cooper: It might be legislation and not 
regulation. 

Mr. Saunders: Legislation is just that much 
more authoritative than regulation. 

Lieut. Cooper: I usually think of "regulation" 
as a regulation of a department. 

Mr. Saunders: I admit that is so in general, 
where you think of something issued by some de- 
partment head or some Bureau Chief. 



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February, 1919 

PRESIDENT WILSON ALWAYS IN 

TOUCH WITH WASHINGTON— 

VIA RADIO. 

(Continued from page 708) 

Lyons Station, France, was established 
long before the Pennsylvania was beyond 
communication range of the United States. 

The Pennsylvania has six receiving 
booths, which were able to receive on eight 
different tunes simultaneously as follows : 
One booth guarded Annapolis or New 
Brunswick tunes 16,900-13,000 meters ; one 
booth guarded Lyons tunes 15,500 meters ; 
one booth guarded Tuckerton's tune 9,200 
meters ; one booth guarded 4,000 meters 
(the Standard arc calling tune) ; one booth 
guarded 450 meters for the U. S. S. George 
IVasliington vacuum tube transmitter tune 
and one booth guarded 297 meters (the 
radio telephone tune). One additional op- 
erator griiarded 600 and 952. 

The radio stations at Otter Cliffs, Maine 
and Lyons, France, were used to receive 
messages from the President, transmitted 
by the U. S. S. Pennsylvania's arc. 

The George Washington's radio equip- 
ment consisted of the following : One low 
power spark transmitting set, one 16,900 
long wave receiving set, one short wave 
6(X) meter spark receiving set, one short 
range radio telephone transmitting and re- 
ceiving set, one vacuum tube 450 meter 
transmitting and receiving set. The U. S. 
S. George Washington was able to inter- 
cept messages transmitted by the Annapolis 
or New Brunswick stations and guard 600 
meter (commercial calling, and emergency 
tune and the radio telephone and vacuum 
ttmes) simultaneously. Messages for the 
President transmitted from the United 
States by the Annapolis, New Brunswick, 
Tuckerton and the Lyons station were re- 
ceived by the U. S. S. Pennsylvania and 
relayed to the George Washington by 
means of radio telephone and vacuum tube 
transmitting sets simultaneously. 

The messages from the President des- 
tined to United States or France were sent 
from the George Washington to the Penn- 
sylvania by the vacuum tube or radio tele- 
phone set and were relayed by the Penn- 
sylvania's high power arc transmitter direct 
to the United States, Lyons or Brest, 
France. 

The radio communication was directed 
by Commander H. W. McCormack, U.S.N., 
Fleet Radio Officer. Lieutenant S. V. Ed- 
wards is in charge of the radio of the 
Pennsylvania. 



ELECTRICAL EXPERIMENTER 



743 



NIKOLA TESLA AND HIS 
INVENTIONS. 

(Continued from (age 697) 

nerve-racking spectacle. Then, inevitably, 
in the stillness of night, a vivid picture of 
the scene would thrust itself before my eyes 
and persist despite all my efforts to banish 
it Sometimes it would even remain fixt in 
space tho I pushed my hand thru it. If my 
explanation is correct, it should be possible 
to project on a screen the image of any ob- 
ject one conceives and make it visible. 
Such an advance would revolutionize all 
human relations. I am convinced that this 
wonder can and will be accomplished in 
time to come ; I may add that I have de- 
voted much thought to the solution of the 
problem. 

To free myself of these tormenting ap- 
pearances, I tried to concentrate my mind 
on something else I had seen, and in this 
way I would often obtain temporary relief ; 
but in order to get it I had to conjure con- 
tinuously new images. It was not long be- 
fore I found that I had exhausted all of 
those at my command ; my "reel" had run 
out, as it were, because I had seen little of 
the world — only objects in my home and 
the immediate surroundings. As I per- 
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ond or third time, in order to chase the 




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appearances Irum my vision, the remedy 
gradually lost all its force. Then I in- 
stincti\ ely commenced to make excursions 
beyond the limits of the small world of 
which I had knowledge, and 1 saw new 
scenes. 1 hese were at first very blurred 
and indistinct, and would fiit away when 1 
tried to concentrate my attention upon them, 
but by and by 1 succeeded in fixing them; 
they gained in strength and distinctness and 
finally assumed the concreteness of real 
things, f soon discovered that my best com- 
fort was attained if I simply went on in 
my vision farther and farther, getting new 
impressions all the time, and so I began to 
travel — of course, in my mind. Every night 
(and sometimes during the day), when 
alone, I would start on my journeys — see 
new places, cities and countries — live there, 
meet people and make friendships and ac- 
quaintances and, however unbelievable, it is 
a fact that they were just as dear to me as 
those in actual life and not a bit less intense 
in their manifestations. 

This I did constantly until I was about 
seventeen when my thoughts turned seri- 
ously to invention. Then I observed to my 
delight that I could visualize with the great- 
est facility. I needed no models, drawings 
or experiments. I could picture them all as 
real in my mind. Thus I have been led un- 
consciously to evolve what I consider a new 
method of materializing inventive concepts 
and ideas, which is radically opposite to the 
purely experimental and is in my opinion 
ever so much more expeditious'and efficient. 
The moment ime constructs a device to 
carry into practise a crude idea he finds 
himself unavoidably engrost with the de- 
tails and defects of the apparatus. As he 
goes on improving and reconstructing, his 
force of concentration diminishes and he 
loses sight of the great underlying prin- 
ciple. Results may be obtained but always 
at the sacrifice of quality. 

My method is different. I do not rush 
into actual work. When I get an idea I 
start at once building it up in my imagi- 
nation. I change the construction, make 
improvements aid operate the device in 
my mind. It is absolutely immaterial to 
me whether I run my turbine in thought 
or test it in my shop. / even note if it is 
out of balance. There is no difference 
whatever, the results are the same. In this 
way I am able to rapidly develop and per- 
fect a conception without touching any- 
thing. When I have gone so far as to cm- 
body in the invention every possible im- 
provement I can think of and see no fault 
anywhere, I put into concrete form this 
final product of my brain. Invariably my 
device works as I conceived that it should, 
and the experiment comes out exactly as I 
planned it. In twenty years there has not 
been a single exception. Why should it 
be otherwise? Engineering, electrical and 
mechanical, is positive in results. There is 
scarcely a subject that cannot be mathe- 
matically treated and the effects calculated 
or the results determined beforehand from 
the available theoretical and practical data. 
The carrying out into practise of a crude 
idea as is being generally done is, I hold, 
nothing but a waste of energy, money and 
time. 

My early affliction had, however, another 
compensation. The incessant mental exer- 
tion developed my powers of observation 
and enabled me to discover a truth of great 
importance. I had noted that the appear- 
ance of images was always preceded by 
actual vision of scenes under peculiar and 
generally very e.xceptional conditions and I 
was impelled on each occasion to locate the 
original impulse. After a while this effort 
grew to be almost automatic and I gained 
great facility in connecting cause and 
effect. Soon I became aware, to my sur- 
prise, that every thought I conceived was 
suggested by an external impression. Not 
only this but all my actions were prompted 
in a similar way. In the course of time 
it became perfectly evident to me that I 



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February. 1919 

was merely an aitloinaton endowed \vith 
power ot movement, responding lo the 
stimuli of the sense organs and thniking and 
acting accordingly. 1 he practical result of 
this was the art of Iclaidoinatics which has 
been so far carried out only in an imper- 
fect manner. Its latent possibilities will, 
however, be eventually shown. 1 have been 
since years planning self-controlled auto- 
mata and believe that mechanisms can be 
produced which will act as if possest of 
reason, to a limited degree, and will create 
a revolution in many commercial and in- 
dustrial departments. 

I was about twelve years old when I first 
succeeded in banishing an image from my 
vision by wilful effort, but I never had 
any control over the flashes of light to 
which I have referred. They were, per- 
haps, my strangest experience and inex- 
plicable. They usually occurred when I 
found myself in a dangerous or distressing 
situation or when 1 was greatly exhila- 
rated. In some instances 1 have seen all 
the air around me filled with tongues of 
living flame. Their intensity, instead of 
diminishing, increased with time and seem- 
ingly attained a maximum when I was 
about twenty-five years old. While in 
Paris, in 1883, a prominent French manu- 
facturer sent me an invitation to a shoot- 
ing expedition which I accepted. I had been 
long confined to the factory and the fresh 
air had a wonderfully invigorating eitect 
on me. On my return to the city that night 
I felt a positive sensation that my brain 
had caught fire. I saw a light as tho a 
small sun was located in it and I past the 
whole night applying cold compressions to 
my tortured head. Finally the flashes 
diminished in frequency and force but it 
took more than three weeks before they 
wholly subsided. When a second invita- 
tion was extended to me my answer was 
an emphatic NO ! 

These luminous phenomena still mani- 
fest themselves from time to time, as when 
a new idea opening up possibilities strikes 
me, but they are no longer exciting, being 
of relatively small intensity. When I close 
my eyes I invariably observe first, a back- 
ground of very dark and uniform blue, not 
unlike the sky on a clear but starless night. 
In a few seconds this field becomes ani- 
mated with innumerable scintillating flakes 
of green, arranged in several layers and 
advancing towards me. Then there ap- 
pears, to the right, a beautiful pattern of 
two systems of parallel and closely spaced 
lines, at right angles to one another, in all 
sorts of colors with yellow-green and gold 
predominating. Immediately thereafter the 
lines grow brighter and the whole is thick- 
ly sprinkled with dots of twinkling light. 
This picture moves slowly across the field 
of vision and in about ten seconds vanishes 
to the left, leaving behind a ground of 
rather unpleasant and inert grey which 
quickly gives way to a billowy sea of clouds, 
seemingly trying to mould themselves in 
living shapes. It is curious that I cannot 
project a form into this grey until the sec- 
ond phase is reached. Every time, before 
falling asleep, images of persons or objects 
flit before my view. When I see them I 
know that I am about to lose conscious- 
ness. If they are absent and refuse to come 
it means a sleepless night. 

To what an extent imagination played 
a part in my early life I may illustrate by 
another odd experience. Like most chil- 
dren I was fond of jumping and developed 
an intense desire to support myself in the 
air. Occasionally a strong wind richly 
charged with oxygen blew from the moun- 
tains rendering my body as light as cork 
and then I would leap and float in space for 
a long time. It was a delightful sensation 
and my disappointment was keen when 
later I undeceived myself. 

During that period I contracted many 
strange likes, dislikes and habits, some of 
which I can trace to external impressions 
while others are unaccoun'able. I had a 



ELECTRICAL EXPERIMENTER 



743 



The Man Who Wouldnt 
Stay Down 




■TEAR OUT HERE- 



He was putting in long hours at monotonous unskilled work. His small 
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He marked and mailed to Scranton a coupon like the one below. That 
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hours after supper. From that time on he spent part of his spare time studying. 

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came another. Then he was made Foreman. Now he is Superintendent 
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ARCHITECT 
Arrhlleptiiral llraflsman 
I'MMBIMil AMI HEATINfl 
Sheet Metal Worker 



□ rHEMICAL ENGINEER 

a SALESMANSHIP 

3 ADVERTISING MAN 

3 Show Card Writer 

3 Outdoor Sign Painter 

G RAILROADER 

a ILLUSTRATOR 

Q DESIGNER 

3 BOOKKEEPER 

BSfenograiiher and Tjpist 
Cert. Puh. Accountant 
Q Traffic Management 
n Commercial Law 

BGOOD ENGLISH 
Common Sfbool Subjects 
a CIVIL SERVICE 
D Railway Mail Clerk 
D STATIONARY ENGINEER 
n Textile Overseer or SupL 

n AiJKicri.TritE 

n Navigator ID SpanUli 

D 1'onrtrvltBtsinK IQ Frf-nch 
C Aniomohlles IH Itnllan 



Present 
Occupation. 

Street 

and No 



City- 



CORE WIRE 

We have been fortunate In securing thru auction several tons of guaranteed pure, double 
annealed Norway Iron Core Wire and are selling this wire to "Experimenter" readers 

At Pre-war Prices 20cts lb. 

This wire Is just the thing for sparlf colls, transformers, etc., and It Is. of course, a very much 
more superior product than the usual Iron wire. We absolutely guarantee the quality. 

If you ever thouglit of building a spark coll. transformer, or similar apparatus, now Is the 
chance to get the right material for It, As far as we know this Is the only lot of Iron Norway Core 
Wire In the hands of any dealer at the present time, and none can be gotten until after the war. 

We have only two sizes left : 

26 INCHES 36 INCHES 

Thickness about No. 21 B and S 

If either of these sizes should be too long we advise cutting the wire down yourself by means 
of shears. It will pay you to do so as real Norway Iron Wire, sold by a few dealers last year, 
brought from 40c to 50c a pound. American core wire now sells for from 30c upwards per pound. 

As long as the supply lasts we offer this wire as described above to our customers at the very 
low price of 20c a pound. Order at once. 

ELECTRO IMPORTING CO., 231 Fulton St., N. Y. C. 



You benefit by mentioning the "Electrical Fxf'cyimentcr" when writing to advertisers. 



746 



ELECTRICAL EXPERIMENTER 



February. 1919 




00 Down 

Brings You A Suit 

Tailor'Made' TO'Order 

Greatest suit offer ever inade! 
Think cf it— for only Sl.OO down we 
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dollar. Send for Style 
Book and see how you can 

Save Half 

Because of our early 
buyinsr in vast quanti- 
tits. our enormous volume 
and direct selling plan you 
actually get your suit at 
• bout half what it would or- 
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mades— don't pay double our 
price fora strictly made-to-or- 
dersuit— a suit that is made to 
fit the lines of your figure per- 
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pives you lone wear and holds 
Its shape. That's the kinH of 
suit you fret from Stanley- 
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5 Months To Pay 

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You wear the suit while naying 
fof it. We trust you absolutely. 
Your worH is all the cecurity w« 
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S 1000 Reward ^J-holT/ovS 

[h;il wt do no: make all our men's 
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. measurements. Some firms try to 
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eimply sell "hand-me-downs" altered here and there. 
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Pl^pir Style Write at once for your free 
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STANLEY-ROGERS CO. 

1015 Jackson Blvd. Oept.sos Chlcaco 




IEarned$2200 



W^ 




Richard A. 
Oldham. He earned $2200.00 
in four months with a Hay- 
wood Tire Repairing outfit. For 
20 years he was telesffaph operator on the 
Illinois Central Railway. He isnow 58 years 
1. He answered my advertisement— quit 
his job— bought a plant and opened a busi- 
ness. He just wrote me "I have made more 
in cisht months than 2' .years as operator." 
There are now 500 stations where tire re- 
pairing is neglected. 

I Must Have 500 Men 

To Fill These Positions 

I have a Bi« interesting Book to send you. 
It tells all about tires— gives 
insl'lefiguresand profit. Send 

f' r -' '. \> hat Ol'JUam and others 
f - . n>r Y'jU. can do. JiVW.O-J to 
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will start you. Th^n open a shop, 
yoac«nBoeba«ino^-.8ttllaround you. 
oat a Haywood Sirn ard business 
coroetoym. Now if t itnrt'^d. Send for 
the Bitf Book and sutrtmuUing mooey. 
M. HAYWOOD, Pr«s. 

Haywood Tire & Equipment Co. 
1209 Capitol Ave. Indianapolisjnd. 




s 



TAMPS: 



50 dlff. BeUlum (large bl-color), China. Jamaica. 
I*<irtuiral. Vene;:uela. etc.. lOc: 100 dlff.. nice 
I acket. 20c: 1.000 well mlled. 40c: 100 Tar. 
L*. .S.. 50c: I.OUO hlOKes, lOc: Aifts. wanted. 50%. 
T.lBt fre.- 1 buy Itampt. L. B. Dover. Overland, Mo. 



YOU CAN'T AFFORD TO BE WITH- 
OUT THESE BOOKS: 

"How to Behave." "Art of Pleating Men." "How to Be- 
come Bejutllul." 25c each. "HynnotUm." 40c. "How 
Gamblers Win." 50c. Satisfaction guaranteed. 
W. A. Engelke. 3257 Bishop St.. CInclnnaU. Ohio. 



violent aversion against the earrings of 
women but other ornaments, as bracelets, 
pleased me more or less according to de- 
sign. The sight of a pearl would almost 
give me a fit but I was fascinated with the 
glitter of crystals or objects with sharp 
edges and plane surfaces. I would not 
touch the hair of other people except, per- 
haps, at the point of a revolver. I would 
get a fever by looking at a peach and if a 
piece of camphor was anywhere in the 
house it caused me the keenest discomfort. 
Even now I am not insensible to some of 
these upsetting impulses. When I drop 
little squares of paper in a dish filled witli 
liquid, I always sense a peculiar and awful 
taste in my mouth. I counted the steps 
in my walks and calculated the cubical con- 
tents of soup plates, coffee cups and pieces 
of food, — otherwise my meal was unenjoy- 
able. All repeated acts or operations I 
performed had to be divisible by three and 
if I mist I felt impelled to do it all over 
again, even if it took hours. 

Up to the age of eight years, my charac- 
ter was weak and vacillating. I had neither 
courage or strength to form a firm re- 
solve. My feelings came in waves and 
surges and vibrated unceasingly between 
extremes. My wishes were of consuming 
force and like the heads of the hydra, they 
inultiplied. I was opprcst by thoughts of 
pain in life and death and religious fear. 
I was swayed by superstitious belief and 
lived in constant dread of the spirit of evil, 
of ghosts and ogres and other unholy mon- 
sters of the dark. Then, all at once, there 
came a tremendous change which altered 
the course of my whole existence. 

Of all things I liked books the best. My 
father had a large library and whenever 
I could manage I tried to satisfy my pas- 
sion for reading. He did not permit it 
and would i\y into a rage when he caught 
me in the act. He hid the candles when he 
found that I was reading in secret. He 
did not want rac to spoil my eyes. But I 
obtained tallow, made the wicking and cast 
the sticks into tin forms, and every night I 
would bush the keyhole and the cracks and 
road, often till dawn, when all others slept 
and my mother started on her arduous 
daily task. On one occasion I came across 
a novel entitled "Abafi" (the Son of Aba), 
a Serbian translation of a well known 
Hungarian writer, Josika. This work some- 
how awakened my dormant powers of will 
and 1 began to practise self-control. At 
first my resolutions faded like snow in 
."Xpril, but in a little while I conquered my 
weakness and left a pleasure I never knew 
before — that of doing as I willed. In the 
course of time this vigorous mental exer- 
cise became second nature. At the outset 
my wishes had to be subdued but gradually 
desire and will grew to be identical. After 
years of such discipline I gained so com- 
plete a mastery over myself that I toyed 
with passions which have meant destruction 
to some of the strongest men. At a cer- 
tain age I contracted a mania for gambling 
which greatly worried my parents. To sit 
down to a game of cards was for me the 
quintessence of pleasure. My father led 
an exemplary life and could not excuse 
tlu- senseless waste of time and money in 
which I indulged. I had a strong resolve 
but my philosophy was bad. I would say to 
him, "I can stop whenever I please but is 
it worth while to give up that which I 
would purchase with the joys of Paradise?" 
On frequent occasions he gave vent to his 
anger and contempt but my mother was 
different. She understood the character of 
men and knew that one's salvation could 
only be brought about thru his own efforts. 
(')ne afternoon, I remember, when I had 
lost all my money and was craving for a 
game, she came to me with a roll of bills 
and said, "Go and enjoy yourself. The 
sooner you lose all we possess the better it 
will be. I know that you will get over it." 
She was right. I conquered my passion 



S kind ervi ken 

Transmitter 

Button 

See what the editor of Elec- 
trical Experimenter says about 
the button : 

New York, Oct. 22, 1918. 
J. Skinderviken, National Hotel, 

Washington, D. C. 

In .writer's opinion, obtained by 
actual elaborate tests, your Trans- 
mitter Button is probably most effi- 
cient device of its kind on market 
today, due to its simplicty and 
other outstanding features. Should 
have a great future. 

H. Gernsback. 

See what a couple of Electrical 

Experimenter readers say about 
the button : 

New Brighton, Pa. 
Dec. 16, 1918. 
Dear Sirs: 

I have been using one of your 
Transmitter Buttons for experi- 
mental work, and it certainly lives 
up to all you say for it and then 
some. 

Yours truly, 
Harry H. Bruhn. 

, Wash, D. C. 
Dec. 18. 1918. 
Dear Sirs: 

I received the Transmitter But- 
ton and I am well pleased with it. 
It is everything you claim it to be 
and more too. 

Youis truly, 

G. A. Wick. 

We have now thousands of 
buttons in stock and can ship 
same day as order is received. 
Send remittance with order as 
per our money back guarantee. 
See our ad page 734. 

We have large stock of neces- 
sary supplementary equipment 
for experimenting. Send for a 
complete list. Receivers $1.00. 
Induction Coils from $0.35. 
Ringers from $0.35. Generators 
from $1.75. 

SKINDERVIKEN 

TELEPHONE EOLIP- 
MENT COMPANY 

2134 North Clark Street 

Chicago. Illinois 
Abbreviated Address STECO 



The ANDERSON 
Steam Vulcanizer 

Anderson's Flexlljle Confor- 
mation Di'vlce. upon which an 
ordinary monkey wrench exerts 
tnn4 or iircssure. forces thou- 
sands of little rubber rWota Into 
the lire's fabric, 
to be cooked In • 

by our super- 
heated dry steam 
Byatem. 

Wo gnarantec to make practi- 
cal nilcarilzers out of men from 
20 to 70 years old. $235 and 6 
to 10 days in one of our many 
State Vulcanizing Schools will 
start you In this profitable 
business. 

Tho Anderson Steam 
Vulcanizer Co. 

No. 23 Williams Bldg.. 

Indianapolis, Ind. '— 

MJtb. of the Frimnug Anderson Steam Vulrantzer. 

erg nf the AnderHfin methnd of vulcanizinff 




INSYDE TYRES Inner Armor 



(or Auto Tlr«i. Doabl« mfl«are, prevent blow- I 
uta and punctarea. Easily aDBlled In «ny tire. | 
'hoaaanda aold. Detaita free. AsenU wanted. I 

Amer.Acceisorlcs Co..P«pt. , 3. Cincinnati j 



You benefit by mentioning the "Hlectrical Experimenter" when writing to advertisers. 



February, 1919 



ELECTRICAL EXPERIMENTER 



747 



I 



then and there and only regretted that it 
had not been a hundred times as strong. I 
not only vanquished but tore it from my 
heart so as not to leave even a trace of 
desire. Ever since that time I have been 
as indifferent to any form of gambling as 
to picking teeth. 

During another period I smoked exces- 
sively, threatening to ruin my health. Then 
my will asserted itself and I not only stopt 
but destroyed all inclination. Long ago I 
suftered from heart trouble until I discov- 
ered that it was due to the iimocent cup of 
coffee I consumed every morning. I dis- 
continued at once, tho I confess it was 
not an easy task. .In this way I checked 
and bridled other habits and passions and 
have not only preserved my life but de- 
rived an immense amount of .satisfaction 
from what most men would consider priva- 
tion and sacrifice. 

After finishing the studies at the Poly- 
technic Institute and University I had a 
complete nervous breakdown and while the 
malady lasted I observed many phenomena 
strange and unbelievable. 

(To he continued in our March issue) 



TEN TELEPHONE OR FORTY 

TELEGRAPH CURRENTS OVER 

ONE CIRCUIT. 

POSTM.\STER GENERAL BURLE- 
SON on December 12th made public 
a letter from Theodore N. Vail an- 
nouncing the invention and develop- 
ment by the technical staff of the Bell 
system of a practical inethod of multiplex 
telephony and telegraphy, which is expected 
to revolutionize long-distance wire com- 
munication. 

Mr. Vail, who is President of the Amer- 
ican Telephone and Telegraph Company, 
explained that there can be a combination 
of telegraphy and telephony under this in- 
vention by which a pair of wires, i.e., one 
full metallic circuit, will be available either 
for five simultaneous telephone conversa- 
tions (ten voices) or ior forty simultaneous 
telegraph messages, or partly for one and 
partly for the other. 

With this new system four telephone con- 
versations over one pair of wires are si- 
multaneously carried on in addition to the 
telephone conversation provided by the or- 
dinary methods. Thus, over a single pair 
of wires a total of five telephone conversa- 
tions are simultaneously operated, each giv- 
ing service as good as that provided by the 
circuit working in the ordinary way. 

Heretofore the best telephone methods 
known to the art provided only one tele- 
phone conversation at a time over a single 
pair of wires. A number of years ago there 
was developed the phantom circuit arrange- 
ment, by which three telephone circuits 
were obtained from two pairs of wires, an 
important improvement, of which extensive 
use has been made commercially. Now, by 
the multiplex method we are enabled to 
obtain five telephone circuits over one pair 
of wires, that is, ten simultaneous telephone 
conversations from the two pairs of wires 
which formerly could be used for only three 
simultaneous telephone conversations. This 
represents an increase of more than three- 
fold in the telephonic capacity of the wires, 
as compared with the best previous state of 
the art. 

Some proposals made by the earlier 
workers in this particular field have natu- 
rally proved suggestive in the successful so- 
lution of the problem, particularly a sug- 
gestion made by Maj. Gen. George O. 
Squier, Chief Signal Officer of the United 
States Army, about ten years ago, and 
which at the time attracted very general 
attention. 

Furthermore, while working in entirely 
different fields and with a different ob- 
jective. Dr. Lee deForest a number of 
years ago invented a wireless device known 
as the Audion, which by improvements and 
adaptation has been made an important part 
of the Bell telephone system. 




Become an Electrician In One Year Here 

Or Learn An Electrical Trade In 6 Months 

THIS school teaches electricity thoroughly, from the very fundamentals, including the 
laws and principles of electricity and the theory of direct current — together with 
practical lectures and problems, actual training in laboratory work and electrical 
machine departments of designing, building, repairing, installing, operating, etc. And the 
faculty here are practical electrical engineers who know how and what to teach because 
they know what knowledge and ability the great field of Electricity requires. 

As one example of this school's thoroughness and 
practical training and development, witness the pic- 
ture above, showing view of armature winding de- 
partment, where students actually wind armature — 
D.C. and A.C. — by a most successfully practical and 
unique method. 

The thorouehness in essentials here, the practical 
training and able faculty, together with this school's 
broad facilities and intensive abilities, are the reasons 
why you can become an Electrician here in one year, 
or master one of the Electrical Trades in 6 months. 

If you nre determined to achieve success in the 
Electrical Field this is your school. You will acquire 
and accomplish more in a shorter time at a less cost 
ami be o. fully developed, practical electrical man when 
you finish. Mail the coupon at the right and get com- 
plete illustrated and descriptive details of the advan- 
tnf:es this school affords. If interested in Electrical 
Engineering with B.S. degree, check same on coupon. 
Mail the coupon now. 

You Can Earn While You Learn 



A STUDENTS' Cooperative Dormi- 
tory and Boarding Club Is organ- 
Ized here with modern and completely 
equipped school quarters for housing 
and boarding students — conducted by 
student committees for the athletic, 
social and academic welfare of the 
students and estahllshtng living econ- 
omy and comfort. Fully explained on 
request. 



Wf 



will provide you with part time employment 
to help defray your expenses here and give 
you actual outside experience — without interfering 
with your class hours — which is fully explained in 
our catalog. Mail the coupon. 



Sch< 



lool of ilngineering 
of Milwaukee 

An Electrical Technicians' Institute 

Department of Practical Electricity 

76-373 Broadway, Milwaukee, Wis. 



I Mail This Coupon NOW 

School of Engineeting of Milwaukee 
I 76-373 Broadway, Milwaukee, Wis. 
I Without obligating rae, please furnish 
I details of . . . .day or . . . .evening course 
. (or courses) checked below. 
I . .Electrician 
. ..Electro-Technician 
> . .Electrical Engineer 
I Special 6 Months' Courses. 

. .Draftsman 
I ..Electrical Trouble & Lineman 

..Electrical Wireman 
I ..Electrical Motor Repairman 

..Telephone Trouble & Repairman 
I ..Electrical Meterman 

. . Dormitory 

' NAME 

I ADDRESS 

I AGE 

EMPLOYED AT 

|l EDUCATION 




TYPEWRITER SENSATION 

PROMPT SHIPMENT. 

$4.00 per month buys a beautifully reconstructed, latest model visible 
typewriter, with back spacer, decimal tabulator, two-color ribbon, etc. 
Every late style feature and modern operating device. Sent on approval. 
Catalogue and special prices free. 

Harry A. Smith, 738, 218 N. Wells St., Chicago, 111. 




Let Me Train YOU in 

AV I AT I O N 



I want you to take up Aviation. Positions at 
good pay are going begging, because there are 
nitt enough trained men to fill them. LET ME 
TK.VIN VOU for some of these big positions 
tli.it pay big wages. I know the game, for I 
liave been flying fur years- My advice to you 
is to deride right now to take a 

Home Course in Aviation ^ ^ ^ — — — """"■" "" 

ill ymir spar*.- time. Send today for our y Fill Out This.Coupon and Mail Today 



Two Airplane Concerns agree to 
take every one of our students 
who have mastered our course 
for the big payinci positions of 
Mechanics. Inspectors. Assemblers. 
Engineers, etc. 
Why don't YOU quality? 



\ personal letter ^ 



Natloual Aero lusrltute, I)ept. 7442, 



^ Morton ISuildiuc Cblciiffo, III. 



alone with it, I will tell you some 

IXSIDB facts abnut this great Indus- - ,. o- n, j -.u . ■_,■ 

trv. Ynu'il want to gel right In. / Pf.^LrS'r: Please send me withoui: obliRstion. copy 
Address aa follows: ^ .^K ^^^ Science of >\vlation also particulars of 

w Mai) Course m the Principles of Aviation, 

Captain George Frederick Capt. Geo. F. Campbell. Chief ^ 

CamuDell. Formerly Third Instructor. NATIONAL AERO / Name - 

Ace of the Royal Flying INSTITUTE. DEPT. 7442. ^ 

Corps. Chief Insnu-tor of Morton building, Chicago. -*^ 
National Aoro Institute. Illinois. 



/ Address „ 



You benefit by mentioning the "Electrical Experimenter" when writing to advertisers. 



748 




Now That The 
War Is Over 



are Needed to Get 
Peace -Time Orders 
to Keep Plants Busy 



$2,500 to $10,000 
A Year for Salesmen 

Factories everywhere have been working day 
and night on war contracts. With peace re- 
turned, these factories must go back to peace 
time work. War contracts require no salesmen. 
Peace lime orders must be produced by sales- 
men. Salesmen will be the most vital factor 
in business. Factories backed by best salesmen 
will be the busiest. Crack salesmen will com- 
mand practically their own price. Prepare now 
for this most essential peace time work. 

Let Us Make You a 

STAR SALESMAN 

We lAUght B. C. Klsler — formerly earning $75 a 
month — has earned as hlgb as J.175 a month as salee- 
man. We taiiaht C. W, Birmingham — former clerk at 
$15 a week — has earned $125 a week as sales manager. 
We taught George W. Reams — rnninrrly earned $60 a 
month — h%<i since earned $306 in one week as a sales- 
man. Our simple course teaches the exact laws of 
successful 84>Uing — making you more efficient than 99 
out of 100 men who learned only through grinding ex- 
perience. We train you In your spare time In your own 
home. $o you can earn while you leam. 

Wonderful 
New Book 



FREE! 



InvM'lcate hy writing for our free book "A Knight 
,f til.- Criji" which telU what our Training and Senice 
-_.^_^_^ will do for you. Let us tell 

\vou about our Free Employ- 
__ -- _-, -.-^ _— ment Department which has 
IVIdll wOUDO il \ consiantly on flle mort' re- 
" \ quests for salesmen than 

/vr PnCTal \ ^^ can possibly fill. WE 

Ul rUaiai \ train you and PLACE 

ai..*i»«^i CI. «»*.»*• N y^'- Write today— Now. 
National Salesmen s • ^^y ^^„r,<, and n^wial 
Training Association \ prir? for limited time. 
Dept 42B \ I^n't Ffrb your whole 

Chicago. Ill', U. S. A. \ f^'^fo by one mln- 

Wlth no obligation on niy part. \ "couVm * or i.iw^al 

send mo jour Big. h ree Illus- \ >;o\V 

trated Book and complete lnfor> % 

mation on vour Training and Free *. Natronti Ssietmtn's 

Emplojnnent Serrica. \ Trimmq tiucoiiin 

Name \ Dept. 428 

\ Chlcaoo, III. 
Street \ U. S. A. 

ciiv V 



AFNESS is MISERY 

] know becaute I was Deaf aod had HeaA 
Noisea for over 30 years. MyioTiiibla 
Aati-teptic£ar Drumt rectoredmy hear* 
iog and stopped Head Noises, and willdo 
it for you. They arc Tiny Megaphonei» 
Cannot beeeen when worn. Easy to put 
in. easy to talteoat. Arc "Unseen Com- 
forts. "I ncrpensiTe. Writefor Booklet and 
my awom etatement o t bow 1 recovcreA 
xnrhMrlnc. A. O. X^EONARD 
Suite 369 70 5th Ave. , N. V. City 

HAVE rouSENT 

for our booklet No, 4, glvinp diagrams and experi- 
ments with the Steco Button? 
STECO. 2134 N. Clark St. Chicago, III. 




ELECTRICAL EXPERIMENTER 

CURING SOLDIERS' ILLS WITH 
ELECTRICITY. 

(CoiitiiiiiL-d pom page 695) 
were 3.000 shell-shock victims ; the day the 
armistice was signed 2,000 o{ them re- 
covered, showini; what a peculiar and 
baffliiis; memal ailment this is. 

The photograph, Fig. 2. was taken at the 
.American Red Cross War Hospital, lo- 
cated at Paignton. Devon. France, which is 
one ol the finest and best eqnipt in the Red 
Cross service. This hospital has a staff of 
1.^0 nurses under the direction of Army 
medical officers. The photograph shows a 
soldier undergoing an electric bath treat- 
ment for rheumatism. This treatment is 
given in the massage room at the hospital, 
where multifarious other electrical ma- 
chines and appliances are to be found, in- 
cluding electrical massage vibrators, electric 
heating pads, etc. 

In some of the larger base hospitals, very 
elaborate electrical equipment has been 
made a\tiilable. In some of the American 
Arm\' liospitals in the United States, where 
the returning wounded are being carefully 
attended to. so as to make them as well and 
strong as they were when they went over- 
seas to fight the Boche, there are some of 
the very latest instruments and apparata 
about which little is known outside of the 
medical profession. This equipment in- 
cludes among other things the Electro-car- 
diograph, which comprises an extremely 
sensitive electrical galvanometer, capable of 
recording the beats of the heart on a pho- 
tographic film, so that the exact condition 
of the heart with regard to its manner of 
beating and its strength, can be minutely 
and accurately studied by the physicians. 

At one of the large New York debarka- 
tion hospitals everything is done by elec- 
tricity — even to the cooking. This hospital 
has one of the largest X-ray laboratories 
in the world, each of the 26 X-ray rooms 
being equipt with a special dark room for 
rapidly developing and finishing the X-ray 
plates. The X-ray in itself has undoubtedly 
saved thousands of lives in the great con- 
flict, in many cases when the victims of 
bullet and shell wounds would certainly 
have died, had it not been for this wonder- 
ful scientific machine. Owing to the ter- 
rific fragmentation (splintering) of the 
shell now used, which often causes small 
steel splinters to penetrate parts of the 
body where they would never be suspected, 
and which, if they were not quickly dis- 
covered by the X-ray, would be quite liable 
to afTect the heart, lungs or blood vessels at 
some unexpected lime and cost the victim 
his life. For this reason the returning 
wounded are most minutely examined and 
X-rayed, especially in the abdomen and 
chest regions, where many of these shell 
splinters, and even bullets, are fond of 
lodging and camouflaging themselves for 
long periods, only to cause trouble at some 
later date, with possibly fatal results. 



THE UNKNOWN PURPLE. 

(Continued from page 690) 
last act, in which scene the hero is visible 
to the eye in flesh and blood but slowly and 
gradually fades away into nothing, leaving 
oidy the purple glow. This was quite im- 
pressive and, of course, was done by the 
usual magician's mirror effect, whereby the 
hero was not on the stage at all, but below 
it, thus casting his reflection on a fine 
screen on the stage : then by manipulating 
the lights in a certain manner the picture 
would dissolve into emptiness. 

Altogether the stage technique is very 
cleverly arranged with an absurdly simple 
effect which in a similar attempt would be 
very elaborate. Outside of that the plot 
and theme of the play is quite out of the 
ordinary and is deserving of mention. 

To show just how different this play is 
from others, reference must be made to a 
note in the program over which audiences 
puzzle themselves until the play itself makes 
the meaning clear. To wit: "The first epi- 



February, 1919 

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February. 1919 



ELECTRICAL EXPERIMENTER 



749 



sode of the last act occurs before the last 
episode of the preceding act." It simply 
means that at that critical time the action is 
going on in two places at once ; and be- 
cause the stage caimot jump back and forth 
in a flash like the motion picture, part of 
the story has to be postponed until the 
scene shifters catch up. 

The illustrations which we present here- 
with are, of course, doctored up for the 
reason that if they were not nothing at all 
would be seen. It is very necessary to 
show the pictures in this manner, otherwise 
we would revert back to our camouflaged 
front cover, — the blank space showing 
nothing, — and as the Editors must show 
pictures — well you know how it is : 
.\ little camouflage here and then 
Is often mightier than the pen ! 



EXPERIMENTAL MECHANICS. 

(Coiitiitued from page 717) 

much more difficult than the ordinary run 
of lathe work. Fig. 5 shows how a crank 
pin, 1, with its rods, is set to be revolved 
between centers 2, 2, of the lathe. This is 
made with provisions for attaching to the 
crank rod 4, 4, temporary support plates 3, 
3, on the ends of the crank shaft, and drill- 
ing center holes in the plates in line with 
the center of the crank pin to be turned. 
The main portions of the crank shaft D, 
D, must first be turned, tho not necessarily 
to their finished size. The plates 3, 3, must 
be bored out to be a tight lit on the ends of 
the crank shafts, to which they are further 
secured by a set screw as indicated. The 
crank shaft is then laid on a surface plate 
or on the lathe' bed, which will answer this 
purpose ver>' well, and the centers of the 
crank pin, 1, determined and carefully 
marked on the supporting plates, 3, 3, so 
that when mounted between lathe centers 
the axis shall pass thru the central axis of 
the crank pin. The center holes should be 
drilled and countersunk in the usual way at 
these points. The crank shaft may then be 
mounted in the lathe on its centers, and one 
end secured to the face plate with a dog 
and the crank pin then turned to proper 
size. 

It will be found in turning crank shafts 
that the work as a whole is very much out 
of balance, and will require a counter- 
balance weight on the opposite side to the 
driving of the lathe. This work will be of 
interest to those building engines, etc. 
(To be continued) 



PRODUCING RAIN BY ELECTRIC- 
ITY AND X-RAYS. 

(Continued from page 687) 

valve rectifiers, is used to produce the high 
potential current for operating the X-ray 
tube, and this current is fed to the tube 
thru the two wires leading up to the bal- 
loon. The X-ray tube itself is placed in a 
light water-proof compartment suspended 
from a spar just below the balloon, as the 
illustration shows. As will be seen, the 
Rontgen-ray tube is so hung that its rays 
are directed upward, so as to impinge upon 
the metallized surface of the balloon, which, 
as will be remembered, is charged at a very 
high potential. Suitable high voltage, strain 
insulators are placed in the lead wires at 
all the points shown. A recording instru- 
ment such as hot-wire ammeter is con- 
nected in series with the high tension lead 
wire. If the ground switch is closed, then 
any static charge in the neighborhood of 
the balloon is conveyed to earth, an indica- 
tion being obtained on the instrument. 
When the ground switch is opened and the 
power circuit closed, the air surrounding 
the balloon for a radius of several hundred 
feet is endowed with conductive qualities 
as a result of the emanations from the 
X-ray tube. When the ultra-high voltage 




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Seven volumes. 3000 pages and 
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DoN^T Senp Amy Noheti 



Write the name of the books you 
want on the coupon and mail it to- 
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If you decide you don't want to keep 
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If you like the books, as thousands of other 



men have after examination, just send us 
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American Technical Society^ De»t. X3382r CiiicafiOi. III. 



American Technical Society^ Depl. 

Please send me set of- 



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— . for 7 days* examination, shipping ch; 

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I press at your expenne. Title not to pass to me until the sec is fully paid tor. 

I yame — — ■ 



Address— 




Vcu benefit by mentioning the "Electrical Experimenter" when writing to advertisers. 



750 



ELECTRICAL EXPERIMENTER 



February, 1919 



414 JPAGES 

[45 ILI/US?PRATIONS 




$1 




ELECTRICITY! 

HERE'S just the book on 
Electricity that you need 
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With this "Little Giant" 1. C. S. 
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an hour or a day need not be lost 
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of the subjects treated are : 

Electricity and Maimetisro : EJectrical Sym- 
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Belts; Shafting; Electroplating; Electrical 
Measurements; Meters; Arc and Incandescent 
Lamps: Mercury Arc Rectifiers; Transformers; 
Insulation; Electric Cars; Single and Multiple- 
Unit Control: Transmission; Rail Welding; 
Tables of Wires — Sizes, Capacities, etc.. — 
Mathematical Rules; Formulas, Symbols; Tablea 
of Constants, Equivalents, Roots. Powers, Re- 
ciprocals. Areas. Weights and Measures; 
Chemistry: Properties of Metals; Principles of 
Mechanics; First Aid, etc. 

The Electrical Engineers Handbook is one of 22 
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charging circuit is closed and the metallized 
balloon surface electrified, then the air in 
the vicinity of the balloon receives a power- 
ful electrostatic charge, which acts on the 
aqueous particles suspended or floating in 
the air in the manner aforementioned. The 
inventor has elaborately cared for many 
problems which might arise in the applica- 
tion of his apparatus, and among other 
things he describes various forms of high 
tension uni-directional current generators 
and means for application against lightning 
discharges. 

The inventor mentions that two or more 
operating stations for rain production may 
be used in cooperation, depending upon the 
observed meteorological conditions, these 
stations being located at greater or lesser 
distances apart. In operating multiple sta- 
tions the degree and sign of the charges 
used therein, respectively, may be varied 
as required. The use of ultra-violet rays 
instead of Rontgen rays for ionizing the 
atmosphere is discust by Mr. Balsillie in 
the description of the apparatus, but they 
are of little practical use, as he points out, 
for they produce practical ionization effects 
only when reflected from a fluorescent sur- 
face. 



r 



EXPERIMENTAL CHEMISTRY. 

{Continued from page 718) 
will contain crystallin deposits. Some of 
the snblimat will be amorphous. 

THE CARBON TEST.— In this the Ar- 
senious O.xid [As-Os] is reduced by Car- 
bon [CO being formed] to metallic Arsenic, 
which sublimes as in Marsh's Test. 

HYDROGEN SULFID TEST. — The 
hydrogen siilfid preciptates arsenious sulfid 
[AssSa] [Yellow] from an acid solution of 
anv arsenious salt 

2AsCh + 3H.S = As,S, J- 6HC1. 

Physiological Effects. 

Like other arsenical comounds, the o.xid 
is very poisonous, the lethal dose being 
about 2;-^ grains, or Ve gram. It is called 
an Irritant poison, and acts rather slowly, 
as the digestive fluids have to transform it 
before absorption. The antidote is freshly 
prepared ferric hydrat [FeCOHJa], to- 
gether with Magnesia. 

2FcCl3 -t- 3-Mg[0H]. = 2Fe[0H]. + 
SUgCh. 
This forms a compound of arsenic insolu- 
ble in the fluids of the body, and precipi- 
tated in the stomach, etc. An overdose 
may act as an emetic. 

For evidence of arsenical poisoning in 
post-morten examination of the liver, the 
stomach, etc., these organs and their con- 
tents are sometimes dialyzed before the 
Marsh and other tests can be applied, in 
order to separate the arsenic from the 
viscera and food products. After being 
treated with Hcl, KCIO3, etc., the finely di- 
vided substances are put into a dialyzer [a 
parchment membrane, see Fig. 156], and 
suspended in water, when the arsenic com- 
pounds, being more diffusive, pass thru the 
membrane in to the water of the outer 
vessel, leaving the other substances behind. 
This outer solution is then concentrated 
and tested for arsenic. Generally, however, 
the contents with the arsenic are dissolved 
in aqua regia and then tested by Marsh's 
or Rcinsch's test. 

Uses. 

It is employed in shot manufacture to 
give a globular form to the grains. 

Cobalt Glance, a compound of Arsenic 
and Cobalt, has considerable use as fly- 
poison under the name of Fly-stone. Ar- 
senic also finds use in many rat poison 
compounds. 

TESTS FOR ARSENIC. 

Marsh's Test. 
Experiment No. 148. 
Make two constrictions in a tube of hard 



BLISS 



Electrical School 

AGAIN OPEN TO CIVILIANS 

FOR A QUARTER OF A CENTURY this 
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SINCE JUNE 15. 1918. the School has been 
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DUE TO THE CESSATION OF HOSTILI- 
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CONDENSED COURSE IN ELECTRICAL EN- 
GINEERING. JANUARY 15, 1919. This 2tith 
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A judicious combination of theory and practice 
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You benefit by mentianinff the "Electrical Experimenter" when ivrtttng to advertisers. 



February. 1919 



ELECTRICAL EXPERIMENTER 



751 



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glass [about 25 cm. long, and 8 mm. di- 
ameter] by the use of a blast-lamp flame. 
The first capillary should be .S or 6 cm., 
from one end, or as near the end as is con- 
venient to hold in the flame ; the second 
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laries should not be less than 4 or 5 mm., 
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upward at an obtuse angle [D]. See Fig. 

157. The opposite end of the tube is next 
fire-polished. When all the parts are cool 
lay the tube down and draw a file gently 
across the middle of the constriction near- 
est the short end, and break it at this point, 
thus leaving a small opening and complet- 
ing the tube E. A drying tube 10 or 12 
cm, lon.g. 8 mm. diameter at each end, with 
bulb, is filled with calcium chlorid, but not 
so full as to clog and prevent the gas from 
passing. This is attached to an Erlen- 
meyer flask of thick glass [about 125 or 
250 cc] and to the arsenic tube. See Fig. 

158. The two-hole stopper of the flask 
carries a thistle tube. The flask may be 
raised on an iron ring stand or other sup- 
port, so as to allow a Bunsen flame, flat- 
tened by use of a "wing-top" to heat the 
arsenic tube, the latter being also sup- 
ported. Not over 5 grams of arsenic-free 
[or C. P.] zinc are put into the flask and 
covered with distilled water. Thru the 
thistle tube are poured small successive por- 
tions of C. P. hydrochloric acid. After 
letting the hydrogen escape for a minute, 
to expel all the air from the apparatus, test 
the gas in the usual way, using the utmost 
caution to prevent an explosion. When sure 
that all the air is expelled, ignite the escap- 
ing hydrogen. Hold the concave side of a 
porcelain dish in this flame a minute to test 
the purity of all chemicals. If no deposit 
is made, pour into the flask not over 5 
cc. of a solution of arsenious chlorid 
[AsCls] or of sodium arsenit [NaaAsOsl. 
Put the Bunsen burner under the combus- 
tion tube, having the top of the flame near 
the capillary, but on the side towards the 
flask. Keep the hydrogen burning well at 
the end of the tube, adding more hydro- 
chloric acid as needed. 

Look for any change of color in the 
hydrogen flame, and in the event of noting 
any, try to explain it. Hold a dish against 
the flame as before. What is the effect, 
and its explanation. Observe any deposit 
in the capillary; describe and account for 
it. 

When there is no further deposit near 
the capillary, and the flame becomes yel- 
low, blow out the hydrogen flame, and 
when the tube is cool, detach it [avoid in- 
haling the fumesi and pour 3 or 4 cc. of 
sodium hypochlorit into the arsenic tube, 
closing the capillary end with the finger. 
See whether the deposit dissolves. This 
test serves to distinguish an arsenic deposit 
from one of antimony, which is insoluble 
in sodium hypochlorit [NaOCl]. Write re- 
actions for: 

1. The action of HCI on zinc. 

2. AsCls on nascent hydrogen, forming 
the DEADLY gas arsin [AsH,]. 

{Continued on page 758) 



POPULAR ASTRONOMY. 

{Continued from page 701) 

thruout the equatorial segment of which 
A-B is a cross-section. 

It should be borne in mind in connection 
with Fig. 1, that space, so far as we know, 
is without limits. Strictly speaking we 
should set no boundary for the universe 
such as is implied when we place a circle 
around the system of globular clusters. 
The region beyond A-B is unexplored. The 
extent of the Galaxy in the direction A-B 
may be even greater than is represented 
here. The limits in Fig. 1 are simply those 
set by the systems of globular clusters. 
When the distances of some of the spiral 
nebulae have been determined it is con- 




ake~"All This 
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You benefit by mentioning the "Electrical Experimenter" when writine to advertiser,. 



752 



ELECTRICAL EXPERIMENTER 



February, 1919 




Don't Be d . 
Sickly Failure ! 



Are you dragging your- 
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your wife given up all 
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No matter what brought you to your present 
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Send for My Free Book 

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Mark the coupon below, sbowlriu what ailments vou 
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LIONEL STRONGFORT 

Physical and Health Specfali-it 
77S PARK BLDG., NEWARK, N. J. 



■ ••>•• .CUT OUT AND MAIL TMI» COUPON • • • - — ■ 

Mr. Lionel Strtmolort. S'rwark. ,V. J. 

I>'-ar S'ronBfnrt: — Plcn*" spnd mp vonr honk "Pro. 
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tjefore the subject In which I am Interested. (776) 

Coldt ..FlatChett . Poor Memory 

..Catarrh Deformity . Rheumatlim 

..Afthma ..Insomnia . .Poor Circulation 

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..Headache ..Short Wind . ImDotenry 

. Thinneu . Flat Feet Vital Losses 

..Rupture ..Constipation Skin Disorders 

. Muscular ..Billiousness . DesDondencv 

Development . Torpid Liver . Round Shcildera 
..Neuritis . Indigestion .. Luna Troubles 

..Neuralgia .Nervousness .. Increased Height 

Vame 



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ceivable that the limits of the celestial 
sphere may be still further extended or 
modified. At present our tentative dia- 
grams of the universe must be in accord 
with the extent of our knowledge at this 
time, just as the maps of the world and of 
our solar system drawn several centuries 
ago were representative of the state of 
man's knowledge in that age. 

The theory that the structure of the 
Milky Way resembles a spiral nebula we 
have considered in a recent article on the 
"Spiral Nrbulai'." The laws governing the 
motion of bodies in a spiral formation are 
not yet known, but the star streams that 
exist within and parallel to the galactic 
plane may be manifestations of the work- 
ings of such laws. New methods of at- 
tacking the complicated problem of the 
structure of the universe and the move- 
ments of the stellar bodies are constantly 
being devised and perfected. The advance 
of astronomy in this direction has been 
very great in the past few decades, and a 
rapid increase of our knowledge in this di- 
rection is to be expected. 

The center of the complete galactic system 
has been located according to Dr. Shapley's 
investigations of the globular star clusters 
in the direction of the richest star clouds of 





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Fig. 1, Above, Shows a Section of the Celes- 
tial Sphere inade by a Plane PerpentJIcular to 
the Plane of the "Milky Way," The Crosses 
Represent the Positions of Some of the 
Globular Star Clusters Projected Upon this 
Plane. The Equatorial Section A-B Is 12,000 
Light Years in Width and 300,000 Light Years 
In Diameter. Midway Between Its Upper 
and Lower Limits Lies the Plane of the 
"Milky Way," the Pole of Which Is at P. 
C Marks the Center of the Entire System, 
and the Globular Clusters are Distributed 
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Sagittarius, near the boundary of Scorpio 
and Ophiuchus. If there is a central nu- 
cleus of the Galaxy, it is to be looked for 
in this general direction which is also the 
center of the system of globular clusters, 
which are symmetrically distributed around 
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this direction also lies the vertex of one of 
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Our own solar system is situated well 
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February. 1919 



ELECTRICAL EXPERIMENTER 



753 



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(The licit installment u-ill af'pear in an 
early issue.) 



A USEFUL ELECTRICAL LABO- 
RATORY SWITCH-BOARD. 

(Continued from page 715) 

are fifteen contacts and they should be 
spaced about Yi," apart. The construction 
is shown in Fig. 8. The rods in both the 
transformer slide and the rheostat are 
mounted on a hardwood or fiber block, the 
dimensions of which are shown in figure 
9. The rod is fastened to the block by 
means of screws or by a long pin thru the 
entire rod and block. The liandle is fas- 
tened by bending a piece of brass as illus- 
trated in the side-view. The contacts are 
six in number and are J/g" thick 1" long 
and i/4" wide. Fasten to the marble with 
No. 8—32 flat-head machine screws counter- 
sunk into the contacts. Make them extend 
far enough behind the board to serve as 
connections. Therefore the heads must fit 
snugly because they will have to carry 60 
amperes of current. 

Next we will take up the construction of 
the transformer. The dimensions are given 
in Fig. 6. The core is built of No. 28 sheet 
iron or stove pipe iron will do. The pieces 
are cut 5" x 1;4" and 2}i" x IVi" ■ Use 
enough to build a core 1'4" thick when 
comprest. The primary for 110 volts con- 
sists of ,S80 turns, 290 turns on each leg, of 
No. 18 D.C.C. magnet wire 

The secondary consists of ISO turns of 
No. 14 or better No. 12 D.C.C. Taps are 
brought out for 1 volt at the fifth turn and 
at every additional five turns until the tap 
for 10 volts is brought out. Then bring 
out taps at the 60th turn, the 90th, 120th, 
ISOth, and 180th turns. These are connected 
to the transformer contacts and the begin- 
ning of the coil is connected to one side of 
the plug receptacle. The other side of the 
plug receptacle is connected to the brass 
rod. But the transformer must he mounted 
first. Figure 7 shows how this is done. 

The rheostat is made by winding No. 18 
iron wire on 6 wooden cylinders three 
inches in diameter and 12 inches long. 
Wind 29 ft. of wire on each. Use nails 
or screws to start and end the winding. 
Connect in series and immerse in water. 
Tap the iron wire connections between each 
coil by using a heavy copper wire and be 
sure to let the copper wire make connec- 
tion below the water. If the water gets 
too low the wire will almost instantly melt 
if it is carrying full load of SQ or 60 am- 
peres. The connections are much the same 
as those of a starting box. Connect one 
side of line to rod and the other side to 
the SO ampere stage plug. Then connect 
other terminal of stage plug to last lead of 
rheostat and connect the first terminal or 
beginning of first coil to contact No. 1. 
beginning of second coil to second contact, 
etc. 

The main-line wires must be No. 1. This 
wire is expensive, therefore the switch- 
board must or rather should be near the 
entrance cut-out. 

A 100 ampere current at 110 volts is 11 
K.W.. and this means the transformer sup- 
plying your house must be of that capacity. 



DRAWING 

V Bi^ Pay- Easy ' 
Pleasant ^ 
Work 



Draftaman earn $150.00 to $300.00 a 
month. The work is pleasant and the 
hours are short. 

You can get Ihid big pay too. AM you need is the 
new 191& edition of theCyclopedia of Drawing and 
a little of youT sp'are time The cost is only 7 cents 
a day. and we give a year's consul ting service free. 
See the FREE examination offer below. 



Cyclopedia of 
DRAWING 

4 big volumes each 6Mx8*i in . bound in gen- 
uine Amaricati Morocco and trimmed in (to'd 
1678 pages and more than 1000 illostrstiona 
plates. dlagram3 and blue prints. 



The only books that thoroughly cover 
Mechanical, Structural and Architectural Drafting 
in a nontechnical way. You don't have to know 
anything about the subject to understand them. 
They begin at the begmning and tell you every- 
thing about Blue print Reading— Mechanical 
Drawing — Machine Design — Machine Drawing- 
Structural Drafting— Architectural Drawing and 
Lettering- Shades and Shadows-Perspective 
Drawing— Freehand Drawing— Pen and Ink Rend- 
ering—Typographical Drafting— Drawing Instru- 
ments and Their Uses and hundreds of other 
things connected with the work. 

Use One 
WEEK 

You can have these books for a whole 
week free without sending one cent. Just send 
the coupon below and all 4 volumes will come to 
you at once by express collect. Use them as if 
they were your own— go through them thoroughly 
and send them back at our expense if you don't 
want to keep them. If you do keep the books 
send us only $2.00. You can send the balance of 
our special introductory price - only $14 80 the 
same way — $2.00 each month. 
Remember you don't take any chances. The risk ia all 
ours and the benefits will all be yours— Send the 
coupon today 

American Technical Society^ 

iVut D 3382 CHICAGO, U. S. * 



raiopEDW.TaflPEUii cyaopoi 

IRAVINOIIRAVIN'- Dr -^ 



ArnQfUan ■ 

Uchnlcal * 

Secl«»v I 

Dept. O 3382 | 
CHICAGO. U.S. A. I 

Please send me the 4-voI- J 

ume Cyclopedia of Drawing % 

>r T days' Free Examination |- 

shipping charges collect. I will % 

send you 02 00 in 7 days and S2.00 , 

each month until the special price of I 

1>1 »0 13 paid, and you will send rne a | 

receipt showing the books are mine. If I 

1 decide not to buy 1 will return the ■ 

books in 7 days ■ 

Name. , £ 

Address ,., ■ ^ m 

References , ■. fc 



Don't Wear a Truss 

BROOKS' APPLIANCB, 
the modem BClentlflc In- 
vention, the wonderful 
new discovery that re- 
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on trial. No obnoxloua 
springs or pads. Has auto- 
matic Air Cushions. 
Binds and draws the 
broken parts together as 
.vou would a broken limb. 
No salves. No lies. Dur- 
able, cheap. 

Sent on trial to provo It. 
Protected by U. S. Patents. 
Catalogue and measure blanks 
matled free. Send name and 
address today. 

C. E. BROOKS, 203B State Street. Marshall, Mich. 

110 VOLT A.C. GENERATORS 
ONLY $5.00! 

Holtzer - Cabot hand gen- 
erators, while stock lasts, 
$5.00. Order today. 

I'.iiltery chargers. 6 v. 6 amp. 
?1(1.00; 7 v. 11 amp. (like 
out) $27.00: Hydro-Elofitric 
(ii'ncrator complete, giving up 
III 25 V. Z^l amp. D.C. $25.00. 
Immediate shipment while 
slink lasts. Order from this ad. 

Watson Electric Co., Dept. 12, Gas BIdg., Chicago 





You benefit bv mentioning the "Electrical Experimenter" when writing to adi<ertisers. 



754 



ELECTRICAL EXPERIMENTER 



February. 1919 




■lllMlllBllMIIMiBlilllBIIIIMMIIIMIllllBlllllPIIIIMIMIIIIMIiMIIIIIIIIMIII 



iiiiBiiiiiaiiigaiiiiiaiiiiiaiiiiiBinaiiiiia 




EXPERIMENTERS ! 

A Sample of What You Can Do With This Outfit 

This Illustration, 

made from an actual 

photograph, shows 

onli' a rery few In- 

strumoDts that can be 

made with the Boy's 

Electric Toys: KKc- 

trio P e n d u 1 u m. 

Electric Telegraph, 

Current Generator, 

Electric 

Dancing 

Spiral, O 8 1 - 

V a n m e ler. 

Space doe3 

not permit 

us to show the hundreds of 

experiments that can be per- 
formed with this wonderful 

outfit. 
The outfit contains 114 separate pieces of material and 24 pieces of 
finished articles ready to use at once. 

Among the finished material the following parts are included: 
Chromic salts for battery, lamp socket, bottle of mercury, core wire 
(two different lengths^ a bottle of Iron flUngs, three spools of wire, 
carbons, a quantity of machine screws, flexible cord, two wood bases, 
glass plate, parafflne paper, binding posts, screw-driver, etc., etc. The 
instruction boolt is so clear that anyone can make the apparatus with- 
out trouble, and besides a section of the Instruction book is taken up 
with the fundamentals of electricity to acquaint the layman with all 
Important facts in electricity in a simple manner. 
We guarantee satisfaction. 

The size over all of the outfit is 14x9x2%. Shipping weight, 8 CC AA 
lbs. No. EX2002 "The Boy's Electric Toys." outfit as described. '?*'•"" 
IMMEDIATE SHIPMENTS 




No. EX2002 

THE BOY'S ELECTRIC TOYS" contains enough material 
TO MAKE AND COMPLETE OVER TWENTY-FIVE 
DIFFERENT ELECTRICAL APPARATUS without any 
other tools, except a screw-driver furnished with the outfit. The box contains 
the following complete Instruments and apparatus which are already assembled : 

Student's chromic plunge battery, compass-galvanometer, solenoid, telephone 
receiver, electric lamp. Enough various parts, wire, etc., are furnished to 
make the ff)llowing apparatus : • 

Electromagnet, electric cannon, magnetic pictures, dancing spiral, electric 
hammer, galvanometer, voltmeter, hook for telephone receiver, condenser, 
teniitive microphone, short distance wireless telephone, test storage battery, 
shocking coil, complete telegraph set. electric riveting machine, electric buz- 
zer, dancing fishes, singing telephone, mysterious dancing man. electric Jump- 
ing Jack, magnetic geometric figures, rheostat, erratic pendulum, electric 
butterfly, thermo electric motor, visual telegraph, etc., etc. 

This does not by any means exhaust the list, but a preat many more ap- 
paratus can be built actually and efft'Ctnally. 

With the Instnirtlnn bonk which we furnish, one hundred experiments that 
can be madf- with this outfit are listed, nearly all of these being Illustrated 
with superb Illustrations. No other materials, goods or supplies are necessary 
to perform any of the one hundred experiments or to make any of the 25 
apparatus. Everything can be constructed and accomplished by means of this 
outfit, two hands, and a acrew-drlver. (Continued In next rolumni 

"The Livest Catalog in America" 

Otir big. new ele<nrlcal cycIor»»'dla No. 19 is waiting for you. PosillToIy 
the mofit complete Wlrelef^ and electrical catalog In print today. 228 Rig 
Pa«p« 600 illufftratlooe. 500 inatrumenu and apparatus, etc. Btg "Treatlie 
on Wircleu Telegraphy." 20 FREE coupons for nur 160-page FREE Wlre- 
l»a Tourw In 20 lessons. FREB Cyclopedia Xo. 19 measures " 
UVijrht H lb. Beautiful itlff covers. 



5%" 




ELECTRO IMPORTING COMPANY 
231 Furton St.. New York City 

I i'T.r]t,^e herewith fl cents In atAmpi or coin for which please 
(ei; I rnt- your latest Cyclopedia Catalog No. 20 as described. 



STATE E.E. 2-10 



The **EIectro" Radiotone 





HIGH FREQUENCY SILENT TEST 
BUZZER 

This Inatrument gives a wonderful high 
pitched MUSICAL NOTE In the receivers. 
Impossible to obtain with the ordinary 
test buzzer. The RADIOTONE is built 
along entirely new lines; it is NOT an 
ordinary buzzer, reconstructed In some 
manner. The RADIOTONE has a single 
fine steel reed vibrating at a remarkably 
high speed, adjusted to its most efficient 
frequency at the ractory. Hard silver con- 
tacts are used to make the Instrument last 
practically forever. 

Yes. the RADIOTONE is SILENT. In fact, It la bo silent that you must 
place your car on too of It to hear Its beautiful musical note. 

You will be astounded at the wonderfully clear, 500 cycle note, sounding 
sharply In your receivers. To learn the codes, there Is absolutely nothing 
like It With the radiotone. a key and one dry cell and ANT telephone, a 
fine learner's set Is had. Two or mure such seta In series will ^ord no 
end of pleasure for Intercommunication work. Shipping Weight I lb. 

Radiotone as described eaeh S,90 

IMMEDIATE SHIPMENTS 

The "Electro" Telegraph 

la not & toy. but a practical, 
honestly built telegraph outfit, 
which not only Boiuids but works 
like the big commercial instru- 
menta. By studying the code 
for 30 days you can become a 
flrst-clasa telegraph operator. 
Huch operators are In big de- 
mand now. Outfit consists of 
TWO complete telejtraph instru- 
ments each measuring 3^ z 2^ 
X 2^. All meUl parts are hiKh- 
ly nickel plated, hicludlng key 
lever. Not© hard rubber knob. 
Telegraph Code Chart, telegraph 
blanks and connecting wire comes with set, but no batteries. Outfit works 
on 2 dr>- cells (one cell for each instrument). The "Electro" is the ONLY 
Outfit tliat works buth ways eai.h station can call; im switches, no ectlras. 
Nothing to get out of order. Guarante*'d to please you or money 

back Price Complete as Illustrated (TWO INSTRUMENTS) 

Shipplna Weight. 2 lbs. 
IMMEDIATE SHIPMENTS 

The **Electro'* Codophone_(/'d^n/j Fniding) 

^^^* * ^ > * ^^K.A 5l 1 f) 

remarkable ^^HUiP St ^ •^^ ^^ 

Instrument Is -^^^^^^^^ 

and does. 

The "Elec- 
tro" Codo> 
phone It 
positively the 
only Instru- 
ment mad 
that will 
Imitate a 500 
cycle note 
e I a r 1 1 y as 
heard In a 
Wireless re- 
:elver. The 

loud-talklng receiver equipped with a horn, talks bo loud that you ean hear 
the sound all over the room, even If there is a lot of other noise. 

THAT'S NOT ALL. By lessening or tightening the receiver cap, a tone 
from the lowest, softest Quality, up to the loudest and hlgbeet screaming 
sound can be had In a few seconds. 

FOR INTERCOMMUNICATION. Tslng two dry cells for each InBtniment, 
two Codophones when connected with one wire and return ground, can be 
uaed for iriternuiuimnicatlon between two houses one-half mile apart. 

One outfit alone replaces the old-fashioned learner's telecrapb set. con- 
sisting of key and Rounder. 

The "Electro" Codophone is a handsome, well made instrument, fool 
proof, and built for hard work. Contacts are of hard silver % inch In 
diameter, that will outlaat the Instrument. 

There Is also a neat code chart and full directions enabling any Intelli- 
gent young man or girl to learn the codes within 30 days, practising one- 
half hour a day. 

Sizes: 6% X 3 X 2%". Shipping weight. 2 lbs. 
The "Electro" Codophone as described, complete 



$1.25 




$1.50 



I 
I 

I 



ELECTRO IMPORTING CO., 

iinaiiiiiaiiiiiamiiBiiiiiBiiiHiiiiiHiiiBiiiiiaiiiiiBiinHiiiiiHiiiii 



231 Fulton Street! 
NEW YORKI I 

IIIBIIIIIBIIIIIBIIIIiaillllHIIIIBlin 



iinS 



You benefit by mentioning the ■'Electrical Experimenter" when writing to advertisers. 



February, 1919 



MT. WILSON'S HUNDRED-INCH 
TELESCOPE. 

(Coiiliintcd from page 703) 

detailed description of the process of fig- 
uring the mirror. Roughly speaking it may 
be divided into two stages. In the first 
stage the mirror was brought to a spherical 
figure; in the second this spherical form 
was charged to paraboloid. The second 
process tho requiring much less time than 
the first involved very great care and fre- 
quent optical tests to avoid the introduction 
of zonal errors. The largest deviation of 
the paraboloid from the sphere in the case 
of this mirror is only one-thousandth of an 
inch. All of the optical work, with the 
exception of the first rough shaping, was 
carried on with wooden tools of va- 
rious sizes and forms, atid the use of 
rouge and distilled water as the polish- 
ing material. 

After the completion of the mirror a 
series of photographic tests was made to 
determine the accuracy of its figure. These 
showed a remarkably high degree of per- 
fection, every portion of the surface hav- 
ing the same focal length to within one part 
in about 90,000. 

A few figures may be of interest in this 
connection. The finished mirror weighs 
4'/! tons, about one ton of glass having been 
removed in the process of shaping and fig- 
uring. Its diameter is closely 101 inches, 
and its thickness at the edge 13 inches. The 
depth of the curve at the center is about 
■ 154 inches. The focal length of the mirror 
is five times its aperture, or 42 feet. .'\ di- 
rect photograph of the moon at this focus, 
accordingly, would have a diameter of 4.4 
inches. As in most modern reflecting tele- 
scopes the 100-inch reflector will be pro- 
vided with two small convex mirrors to be 
attached to the upper end of the tube, either 
of which may be utilized to increase the 
focal length in much the same way as 
telephoto lenses are used in ordinary 
photography. With these mirrors focal 
lengths of 134 and 251 feet may be ob- 
tained and the magnification corre- 
spondingly increased. 

As soon as. the optical work upon the 
mirror disk was fully under way the de- 
sign of the telescope mounting was begun. 
In view of the great size and the immense 
weights involved the "closed fork" type 
was finally adopted. In this form of mount- 
ing the telescope tube is hung in the center 
of a rectangular frame of massive steel 
girders, the bearings providing for north 
and south movements of the tube being 
built into the two side members. The en- 
tire rectangle is mounted on bearings at 
top and bottom, which furnish the east 
and west motion of the telescope. To re- 
live friction the system of mercury flotation 
used most successfully for the 6b-inch re- 
flector is employed, there being two large 
steel floats and corresponding mercurv' 
taiiks, one at either end of the rectangular 
axis. These floats carry about 98 per cent 
of the moving parts of the telescope, or 
some 90 tons, the remaining two per cent 
being carried by two large spherical defin- 
ing bearings. The instrument is controlled 
by electric motors, which provide for three 
rates of speed in both north and south and 
east and west directions. 

The driving clock which moves the tele- 
scope at a uniform rate corresponding to 
the rotation of the earth is placed within 
the concrete pier which supports the 
instrument and near the south end. The 
driving shaft extends from the clock and 
meshes with a worm wheel 17 feet in 
diameter, which is attached to the tele- 
scope axis. 

The building and dome which enclose the 
telescope form a steel structure 100 feet 
high and 95 feet in diameter. The walls 



ELECTRICAL EXPERIMENTER 



and roof are double thruout to admit of 
the free circulation of air, and thus help to 
equalize the temperature within the build- 
mg. The shutter is of the double section 
type, divided in the center, and when fully 
open provides an aperture 20 feet wide. 
Like the observing platform, the crane hoist 
and the dome mechanism, it is operated by 
electric motors. The dome is mounted on 
24 four-wheeled trucks running on specially 
ground rails, and power is applied by two 
driving trucks at opposite sides. When ro- 
tated tho motion of the dome has been 
tound to be remarkably smooth and free 
from vibration in spite of the great weight 
involved, which is approximatelv 600 tons. 



755 




Wanted-Railway Mail Clerks 



$1100 to $2000 
Year 



Common Edu- 
cation Suffi- 
cient 



/ FRANKLIN INSTITUTE 

y Dept 8101. Rochestor. N. Y. 

. Sirs; Sftid uie, wllhoul cliarne. 

C^ ^1) sample KaUttay Mall Clerk 
Sure Pav LIIa Ci* Wr a mi iiauoii queauuus: ci) sched- 
Job Pun^lln- <•? "'" showing places of »U U. S. Gov- 
necmaVv > nt'^T"" ''™"'« ""nloatlons; (3) list 
necessary, y ot other government jobs now open, and 
Age (6 y (4) free book dest-ribing them 

t<"M) / .Name 

—^■^^ .Address 




STORAGE BATTERIES FOR ALL PURPOSES ^.^ 

Better Batteries for Less Money ^^-^--CTl^^ 



Backed by An Exceptional 
Guarantee 



THE MARK O' 
QUALITY 



«r*^ 



9^ 



w 



tiS 



©« 



V* 



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FOR 



Capacity 
Qualityf Price 

A SPECIAL MARKO STORAGE BAHERY 
EACH MAKE OF AUTOMOBILE 



PAHLM.MARKO & CO.. Int.. 140M412 AU.n.ic A«. Brooklyn, N.Y. N. T.D.p.i-974 gtb At... N. Y. Cit, 



YOU HAVE A BEAUTIFUL FACE 

BUT YOUR NOSE ? 




BEFORE 

IN THIS DAT AND AGE attention to your appearance 
Is an absolute necessity if you expect to make the most 
out of life. Not only should you wish to appear as 
attractive as possible, for your own self-satisfaction 
which is alone well worth your efforts, but you will find 
the world in general judging you greatly, If not wholly, 
by your 'lookt." therefore it pays to "look your best" 
at all times. 




AFTER 

^ZT^imt?",' '?, '" *?" !""<'"" »tli«n»l«»: It wlU Injure 
??.t. ^hl'Vl ^^" ""0 Impression you constantly make 
rests the failure or success of your life. Which is to be 

(ion i,?i „""f',' "°\ ill-shaped noses without opera- 
tion, quickly, safely and permanently. Is pleasant and 
at night '"'"'"" "'"' """'^ "^^'ly occupation, belSg w^rS 
Wrllt today !or /,« bookld. which tell, you how lo corTcd lllshapal noia without mt If not taUtUclory 

M. TRILETY, Face Specialist 1038 Ackerman BIdg.. BIngliamton, N. Y. 



S^ n d N O Mo II e V ! 



Just send coupon below and -we vifill 
forward your shoes at once I They 

are the greatest shoe values ever offered. We 
are glad to send them NO MONEY IN AD- 
VANCE because they are built so full of wear 

and are so comfortable .ind so good looking that we 
know when you once see them you will want to 
keep these wonderful shoes. Send no money— mail 
the coupon only and shoes will come at once. 

NATIONAL WORK SHOE 

Direct to You from the Shoe Market 

of the World 

[■i ll- That Ls why ihe price is only 

XtBSi ^ $3.65. Why pay $5 or $6 ? 

nlB^^HHHHSS ^I'P these shoes on in your 
v^^^^>S!^^Hi^H ottii hniue. Note Ihe splpn- . 
did seltxned leather" ~ " 




NATIONAL DRESS SHOE 

Smart and stylish. Genuine oak leather soles. 

Broad low heels. Extra quality uppers. 

These gooU-looking, dressy shoes are built f.ir 

n\e toes and comfort. Our price oiiJv 

13.85. Compare them with the 

best J7.00 shoe you ever saw. 

You miist see them to arpre- 

cJate their wonderful Slvle. 

Quality. Workmanship. S'oii 

miist try them on to enjoy their 

absolute Comfort. Thai 

why we send them to you- 

no money In advance.' 

Sent on approval. The 

s h 11 es must convince 

YOU. Act NOW! Sen 

coupoD at once. 



Feel 
w Eiift and easy they are on your feet I 
Examine the "Indestructo" heavy leather 
Customers write: "These shoes look 
cnod after 6 months of hard wear." 
If they aren't the beat work shoe 
you ever saw, send them back and 
we'll return your money. You are 
tho judge of the Style, Comfort and ,^^.=_^_^ 

Quality. Use coupon TODAY * ■ ■ » »^^^^^^^ Send NO Money } 

and get your pair nf thesf I _ ■■■*■»•■ — — «»•■■»« 

wonderful shoea while this | Boston Mail Order House, Dept SIS 

special offer holds gOiHL | Essex P. O. Building, Boston, Mas*. 

cr*MT\^^ ■ ^^^ postpaid shoes marked below. I will 

OtllU^^^^ I P^y '**'■ ^hem on arrival. If they are not 

the best value in America, you will return 




Ovlv this cou- 
pon, no jiioji'T/. 
It brw(H! these 
splendid s/ioes 
to you prepaid. 



my money. I risk nothing. » 

J □ Work Shoe, |3.65 I Q Drasi Shoe. $3.85 

■ Size Color Isize 



BOSTON MAIL ORDER HOUSE, Boston, Mass. 



I N'ame 



^^1 Address 



Vou benefit by mentioning the "Electrical Experimenter" when writing to advertii 



756 



ELECTRICAL EXPERIMENTER 



February, 1919 




Opportunity Ad-lets 



You will find many remarkable oppormnitiM and real barirains in these columns. It will pay you to read and investigate the offerings 
made everv month bv reliable firms, dealers and amateurs from all over the country. No matter what you may be seeking, whether supplies, 
automobile accessories, the opportunity to make money, or anything else, you will find listed here the best and most attractive specials ot the 

"'° Advertisements in this section seven cents a word for each insertion. No advertisement for less than 50c accepted Name and address 
must be included at the above rate. Cash should accompany all classified advertisements unless placed by an accredited advertising agency. 
Ten per cent discount for 6 issues 20 per cent discount for 12 issues from above rate. Objectionable or misleading advernsements 

accepted. Advertisements tor the March issue must reach us not later than January 22. 



not accepte 



The Circulation of the Experimenter is over 100,000 and climbing every month 

EXPERIMENTER PUBLISHING CO.. INC.. 233 Fulton Street. New York, N. Y. 



m <i:inii'<'i uiMiiiiii.ii.iimiiiiiiiiiiiitiNiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiaiiuiiiaiiiiiiimiiiiNiiliiiiiiiiil^ 

.-lutomobile Accessories 

More Power. Less Fuel, No Carbon. No mys- 
tery, plain lacts, results guaranteed. Write for 
booklet. S. O. Automobile Accessories Co., Balti- 
more, Md. _^_ 

Fords Start Easy in Cold Weather with our 
new 1919 carburetors. 34 miles per gallon. Use 
cheapest gasoline or half kerosene. Increased 

f>ower. Styles for any motor. Very slow on 
ligh. Attach it yourself. Big profits to agents. 
Money back guarantee. Thirty da>;s' trial. Air- 
Friction Carburetor Co., 270 Madison, Dayton, 
Ohio. 

Vulcanize on Anderson Steam Vulcanizer. See 
Advertisement. Page 736. 
ilDni:!T:-:7miiiiiiiiiiiiim:i!miiiiHiNiiii!iiltiiiii'nit!!ililiinililliiiliiiiiii(im^^^^^^ 
Motors. Engines and Dynamos 

dmall Motors and Generators: 1000 New Motors 
and Generators from Bankruptcy Stock, J-i H. P. 
A. C. $18.50 each; 1 2 II. P-. $3000. Batterv 
Charginff Sets— Robbins & Myers new outfits, all 
sizes. S30.00 each and up. Charging, Lighting 
and Moving Picture Arc Generators. $10.00 each 
and up. Motors for all phases of current. Im- 
mediate delivery. Less than Yi regular prices. 
Write for late bulletin. Johnston, West End. 
Pittsburgh. Penna. 

Small Gasoline Engines, ^4 H. P. $20.00. Drives 
D\ namo. Washing Machines. Air Brush, etc. 
Honest Abe, 528 S. TayjOTi^Ave^^_Oak_^arkjjnL_ 

Motorcycles 

Motorcycles from $2S up-New and second- 
hand. K.-isv lerms, large list to choose from, all 
makes. Send 4c stamos for Bulletin "A." Peer 
less Motorcycle Co., Watertown. Mass. 

Motorcycles, all makes. $25 up. New Bicycles 
at big reduction. Secondhand, $8.00 up. Motors. 
Motor attachments, Cvcle Motors. Smith Motor 
Wheels, etc., $20 up. New parts to fit all makes 
carried in stock. Second-hand parts good as 
new, 5oCr discount. Expert repainne on magne- 
tos, generators, transmissions. Motors over- 
hauled $10.00 up. Henderson Motors our spe- 
cialty. Write for Big Bargain Bulletin. Amen- 
can Motor Cycle Company. Dept. 17, Chicago. 



ny. IJept 



Help Wanted 



Men Wanted to make Toy Soldiers, Army, 
Navy, and other toys. Homeworkers on small 
scale, manufacturers on large scale. Greatest 
chance for industrious people for independent 
business. Enormous demand and future in 
"American -made toys". This new American 
work stands out conspicuously. Factories have 
been established, people trained, machinery made 
with energy and success. Dealers don't want to 
handle anv others except "American-made". \Ve 
buy these goods all year, paying fixed prices. 
Experience or tools not necessary. Hundred and 
more made complete per hour. Casting form out- 
fits S3 up. Booklet and information free. Toy 
Soldier Slanufacturing Co.. 32 Union Square, 
New York. 

To Ascertain the Vocation for which you are 
best adai>tcd send for Zancig's Revised Horo- 
scope. Send date of your birth and 25c. Prof. 
Zancig. 109 West 87th St.. New York. 

Business Worth While. I Start You silvering 
mirrors. Platinc tableware; Plans Free. Clar- 
ence Sprinkle. Dept. 48, Marion, Indiana. 

Thousands Government Peace Jobs open to 
men— women girls. $900 to $1500 year. Short 
hours. Paid vacations. Common education suffi- 
cient. List positions free. Write immediately. 
Franklin Institjite;_^eEt^_B26;_Rochestei\_2LJL_ 

Soua Form s Wanted 

Write the Words for a Song. We write music 
an<i guarantee publisher's acceptance. Submit 
poems on war. love, or any subject. Chester 
Mu^ic Co.. 538 S. Dearborn St., Suite 265, Chi- 
cago. 



Telegraphy 



Telegraphy, Wire and Wireless, and Railway 
Acr^'-ntinff taucht thoront'hlv. I'VPRFCE- 
DENTED DEMAND for both sexes. BIG SAL- 
ARIES. Oldest and Larges* School— ^-^t. a^ 
years. Catalog free. Dodges Institute, Seventh 
St., Valparaiso, Ind. 



toiiimiimuDiiiuiiui 



.-hiciits Jl'a)itrd 



Insyde lyres, inner armor tor automobile lires, 
double mileage and prevent punctures and blow- 
outs. (Juickly applied. Costs little. Demand 
trementlous. Prohis unlimited. Details free. 
American Automobile Accessories Co.. Dept. 54, 
Cincinnati, O. 

Hel-Met The Kaiser Pin^Latest war novelty. 
Biggest hit out, every patriotic citizen^ wants 
one. Sample loc. Wedge Mfg. Co., "KM," Bing- 
hamton. N. V. 

$10 Daily refinishing chandeliers, brass beds, 
automobiles by new method, without capital or 
experience. Free particulars and proofs. Write 
today. Gunmetal Co.. Ave. D. Decatur, III. 

|iililiiiliiiiilililtlliillllllllllll(lllliilllllllllllllllllllllllllllllllllllllilillitlil)llllll)^ 

I Charlotte, N. C. | 

I Oct. 4, 1918. I 

I Electrical Experimenter Pub. Co., y 

I 233 Fulton St., New York. = 

i Dear Sirs: i 

I It certainly was SOME RESULTS. | 

H I've almost worn out a good typewriter. = 

H Just about exhausted myself writing, g 

m Used all the paper in this part of America. | 

g And about Gone Busted buying postage ^ 

1 stamps. _ E 

i . Now, I'm a-goina quit, and will never do g 

E it again, or at least I won't promise to an- g 

i swer all the letters I received from an Ad = 

i that I put in the "E. E." f 

I The letters are still coming in. — The = 

i apparatus advertised has long since been g 

i sold. Every piece of it. The letters are | 

i from all over the United States. AND § 

I ELSEWHERE. Received one today from | 

f Shanghai, China. Can you beat that. I'm g 

f enclosing the letter from China. g 

= It's a great life, if you don't weaken. b 

I I wish to THANK the "E. E."— Some i 

f circulation. ^ 

§ Very Respectfully, | 

I G. R. SMATHERS. I 

I 403 N Brevard St., Charlotte, N. C. | 

ilUlllllllllllll11llllllllllllll<llillll1lllll<lilil<lllliHilllllillllllillliilllllllliltllllllllllllllllllllllllllllllllllll]iailll^ 

Exchange Ads 

Sell Cheap. Train, Radioptican, lot of small 
stuff. 242 drove St.. Melrose. Mass. 

Trade ($8.00) Rexo Junior Camera for \'. P. 
Kodak. Sf ust be in good condition. Morton 
Wienert. 404 Bay St.. Taunton. Mass. 

Sixty Inch High Frequency Lecture Set. Cost 
S200. line. Price reasonable. J. W. Manghmer, 
Newman. 111. 

For Sale. Good Holtzer-Cabot late model mul- 
tiple glass plate Static machine, no motor. See 
cut Experimenter, September, 1915. issue. Eight- 
een month use. First money order for $65.00 gets 
it. Ready for shipment, with accessories. Everett 
Leo Deeter. Norcatur. Kansas. 

Trade. Business College Course. $20 paid for 
Wireless Instruments. Particulars, Leroy Hobbs, 
Albion, Nebr. 

Wireless Instruments for Exchange. 5000 miles 
receiving cabinet for damped ami undamped wave 
reception, audion cabinet, commercial type peri- 
kon detector. 80 ampere Thomson ammeter. 2000 
ohm radio phones, powerful Tesler Coil. 50 watt 
generator. Want VVeston D.C. ammeter, volt 
meter, A.C. volt meter, wattmeter and muUi 
range meters. What have you in this line. All 
answered. Samuel D. Cohen. 281 



correspondence an 

Wyona St., Brooklyn, N. Y. 



For Sale, '/i K.W. Transformer $8.00. Secondary 
7000 volts, also large variety of switches. P, 

Crawford. 1310 Broeck St.. Albany, N. Y. 

For Sale. 1/2 price, 2000 ohm phones, $4.50; volt 
and ampere meter 175 A 90V. D.C. $15.00; J/^ coil, 
$1.25; snocker, 75c; buzzer horn, $2.50; size io'/4 
hockeys, $2.00; the following new. never used 
20.000 meter couplers. $15.00; rotary gaps. $10.00 to 
$15.00; lightning switches 100 A. 600 V. marble 
base, $3.00; 500 mile receiving set, $15.00. Harold 
Hammer, 3225 23 Ave.. So. Minneapolis. Minn. 

For Sale. Pope motorcycle engine, excellent 
condition; Bosh magneto. Schehler carbureter. 
Fine for small shop if fitted to base. Price, $25.00. 
O X. W'ebb. 1923 Hayes St., Nashville, Tenn. 



omiBniflinimiiniiouuuiiDinmiiDniDiiiiniiDii 

Exchani^t' .-Ids 



-Cont^d 



Thirty Dollars taktrs Radio cabinet Transform- 
er, Condensers. Phone and large Omnigraph. 
Savage, 820 Beverly Rd., Brooklyn, N. Y. 

Have .22 Marlin pump-action rifle; chemicals. 
Want closed-core transformer, Murdock moulded 
condensers, no A.C. meters. Pray, 102 Heath, 

Somerville, Mass. 

Sell. Good Smith Premier typewriter $25.00. 
Wilkes Dearing, Covington, Tenn., Route 2. 

Swap. New Auto Knitter Hosiery Machine and 
accessories for mortorcycle or anything you have, 
all answered. David Zilman, 10 Lisbon St., Mai- 
den. Mass. 



For Sale. Sigwalt Printing Press No. 10, two 

borders, two sets of type, complete, $15. John 
Abderholder. 1115 Summit Ave., Jersey City, N. J. 



Bargains. I'lat backed mandolin, nearly new, 
excellent tone, $5-25; giant sounder, $1.00; Erector 
motor, $1.50; Enos Johnston, 9 Rutherford St., 
Binghamton. N. Y. 

Sell. 2000 ohm phones, headband, 8 ft. cord, 
$4.50. Never used. K in. spark coil. 75c. Post- 
age extra. N. E. Ristey, 707 8th Ave., S. E.» 
Minneapolis. Minn. 

For Sale. One I. C. S. Electrical Reference Li- 
brary. Best offer takes same. J. H. Rappold, 
Newport News, Va. 

Sell. 3 H. P. single, motorcycle engine, $5. 
Fan induction motor no V., $4; and others. Most 
anything electrical or wireless very cheap. Write 
me. Nowell Rang, yy S. Spencer. Aurora, Illinois. 

For Sale. Omnigraph Spring motor hardly used, 
4 dials. E. N. Davis, Antrim, N. H. 

Here They Are. Baloptican. High grade Bausch 
X: Lomb Model C instrument, with attachment 
for opaque objects, and carrying case; good effici- 
ent Hoover Suction Sweeper; fine large Lionel 
Electric Train outfit; E. I. Co. Telsa Trans- 
former; game board for 56 garnet, with revolving 
table; Baldwin Camp Lamp; 6 in. Red-Devu 
Water Motor. All the above in best condition, 
at money-saving prices. First come, first served. 
Be first. State very exactly what you have in 
Wireless goods. Vernon Chaberd, 362 Custer 
Ave.. Youngstown. Ohio. 

For Sale — J4 H.P. Gasoline Engine. $30.00; Gen- 
erator, no volts, deliver 100 watts, $10.00. B. 
Hoinacki. 14^ W. Superior St., Chicago. 111. 

Radio Operators: Troubles and probable 
causes. Source of power to antenna, each sub- 
ject covered fully. Pamphlet tells you how to 
locate trouble. Advice from ten years' experi- 
ence for 25 cents. Order while they last. E. 
Jones, 818 Roosevelt. New Orleans. La. 

$65.00 Course in Aviation complete with blue 
prints, $12.00. Robert White, Madison, So. Dak. 

For Sale — Motorcycles. Printing Outfits. En- 
gines, Typewriters, etc. Sold on monthly pay- 
ments. We buy. Catalogues, lo Stamps. Sun- 
shine Exchange Agency, Dept. EEi, Port Huron, 
Michigan. 

Must Sell— Wireless and Electrical apparatus. 
Send stamps for list. Marcel Scharer, no West 
8(jth St., New York City. 

For Sale — Electrical apparatus. Send stamp for 
list. M. Grain ger, Kinston. N. C. 

Wanted— Small lathe, screw cutting. Will pay 
cash. Will sell small "Goodell" lathe. Andrew 
Ellison, Kir ksville, Mo. 

Wanted— Wireless apparatus. Swap $7.50 Erec- 
tor. Chemistry books. Write. Milton Plegge, 
4464 Natural Bridge, St. Louis, Mo. 

For Sale — Cyclopedia of Applied Electricity used 
three months. Will sell for $16. William Wol- 
fram, 31 Norris St.. Lawrence. Mass. 

Will Exchange — $45 course in Aeronautics with 

blueprints, for Electrical or Chemical Books, or 

Mi'-rf'S'-opc. Chas. Jeffries. Lake Charles, La. 

■B Ui i iMM i iMiumii iiii i JimnTiiTnininniniiimitrrtiiitiiiiniiiniiiniiiiiiiiwiiiniiniiiiiiiiiniiiniiiiiitm^ 

Sc enery for Hire 

Collapsible Scenery for all Plays. Amelia Grain, 
Philadelphia. Pennsylvania. 



Ynu benefit by mentioning the "Electrical Experimenter" when writing to advertisers. 



February, 1919 



ELECTRICAL EXPERIMENTER 



757 



■maoiimiiiniimuaiiiBuii 
Books 



Free — $5,000 worth of valuable books as pre- 
miums. Write ior more information and cata- 
logue; it's fret. 1 have many books on Natural 
healing, personal magnetism, Clairvoyance, seer- 
ship, Hypnotism, Mesmerism, concentration, 
character reading, mind power, etc. Tell me your 
wants. A. W. iMartens, JX8. Burlington, Iowa. 

World-Romic System, Masterkey to All Lan- 
guages. Six Textbooks, $1.44. French Chart, 37c; 
Spanish, 37c; Aviation Dictionary, $1.50. French- 
English Aviation Dictionary, bic. Languages, 
143 West 47th. New York. 

Allen 
Banaits", 



Diiinimtiiiiiii[iiiiiiiiiiiii]iiiiiiuiiiuLniii[m]]iiii]ia]i]ii]nnuMii»iMWLiiwimufii[pumiinnMiniim 



Miscellaneous 



"James Boys'\ "Younger Bros.", 
Gang", "\'illa the Bandit", "The Auto J 
"Harry Tracy", "Dalton Gang", "Jeff Clayton", 
"Behind the Scenes", "Rube Burrow", 25c each 
postpaid; rare Fiji Island newspaper with each 
aollar order. Q. K. Publishing Co., Decatur, 111. 

Scientific, Technical, Engineering^ Industrial 
Books. February list, 3c. Klaus, Eureka, 111. 

Leading Magical Magazine. Y'ou'll like it! All 
magicians do! W' hy ? The value is there. 
Sample, 10c; three months, 25c; year $1.00. The 
Eagle Magician, Dept. E, Minneapolis, Minn. 

What Every Draftsman Should Know. Very 
useful booklet. Price 12c postpaid. Wack Book- 
let Co., 1943 Patten St., Philadelphia, Pa. 



Books on Sex. 

Springfield. 111. 



Catalog free. United Sales Co., 



Books for Real Live People. Lists free. J. E. 
Sheridan. 417 E. 151st., New York. 

How to Locate Oil, Minerals and Valuable Sub- 
stances by Wireless; Scientific Book, $3 postpaid. 
Astral Child Publishing Co., Corpus Christi, 
Te.xas. 

To Get Better Pictures: Read the Amateur 
Photographer's Weekly; illustrated; weekly prize 
competitions; print criticisms; many unique fea- 
tures; $1.50 per year; three months' trial sub- 
scription 25c. Abel Publishing Company. 401 
Caxton Bldg., Cleveland, Ohio. 

Old E. E. Back Numbers: We have some valu- 
able old E. E. back numbers on hand as follows: 
J915 — Jan., March, April, June, July, Aug., Sept.. 
Oct., Nov., Dec, price each 35c. 1916 — Jan., Feb., 
March, May, June, August, Sept., Oct., Nov., 
Dec, price each 35c 1917 — Jan., Feb., March, 
April, May June, July, Aug., Sept., Oct., Nov.. 
Dec, each 35c 1918 — Jan. 35c; Mar., May, June, 
July, Aug., Sept., Oct., Nov., Dec, each 20c. 
Jan., 1919, 20C We can fill orders at once upon 
receipt of your remittance, and if you have not 
these numbers already, now is your chance to 
get them, as they probably will be snapped up 
very quickly. Experimenter Publishing Co., 233 
Fulton St., New York City. 

^gmi^inmwu—miinniniiini.i [rmiiLiiN [iiiiniiiiiiiiiiiiintiiniiimiininniiitr 



Patent Attorneys 



Patents — Fees payable in monthly installments. 
Send sketch for free report. Books free. Frank 
Fuller. Washington, D. C. 

Patent Your Own Inventions. Save attorney's 
fees ; we prepare applications ; furnish full in- 
structions and give satisfaction. Free informa- 
tion. Carl Larsen Co., Park Row Building, New 
York City. 

Patents. My fee payable in installments. Full 
particulars return mail. Send sketch for report 
on patentability. John Patton Duffie, McGill 
Building. Washington, D. C. 

Millions Spent Annually for Ideas! Hundreds 
now wanted! Patent yours and profit. Write to- 
day for free books — tell how to protect yourself, 
how to invent, ideas wanted, how we help you 
sell, etc. 212 Patent Dept., American Industries, 
Inc., Washington. D. C. 

M. F. Miller, Ouray Building, W'ashington, D. 

C, Patent Attorney. Mechanical and Electrical 
Expert. Best quality of work and results. Mod- 
erate charges. Advice free. 

Your Idea Wanted. Patent Your Invention. I'll 
help you market it. Send for 4 free books, list 
of patent buyers, hundreds of ideas wanted, etc. 
Advice free. Patents advertised free. Richard 
B. Owen, Patent Lawyer, 130 Owen Bldg.. Wash- 
ington, D. C, or 2278T WooUvorth Bldg., New 
York. 

Inventors! We have a proposition that will 

probably interest you. Inquiries Invited. The 

Wakefield Engineering Co., 922C F St. N. W., 
Washington, D. C. 

Fortunes from Patents are made only from a 
good invention strongly protected. Send Sketch, 
or model and $5 for thorough search and 
honest opinion of patentability. I give personal, 
conscientious and expert service. Lester Sargent, 
Patent Attorney, 524 Tenth Street, Washington, 

D. C. 

Inventions Patented; Trade- Marks Registered; 
Labels, Prints and Publications Copyrighted; 
reasonable fees. Correspondence solicited; de- 
tailed information free ; booklets. Jaynes & 
Taynes, 702 Kellogg, Washington, D. C. 
uniUBnmnnmmmitnminRiimitiniinntmmmimmniimitTniiroinmnBiniitrDumTnDirmimiini 
For luveniors 

Inventions Commercialized. Cash or royalty. 
.-\dam Fishi^-r Mfg. Co., 205 St. Louis. Mo. 

Inventors — Market and secure your inventions 
through National Institute of Inventors. World 
Bldg., New Y'ork City. Membership co-opera- 
tive organization. 



Luminous Paint makes watches, clocks, any- 
thing visible at night, 25c bottle. Luminous 
Paint Co., 2426-X Folk St., Chicago. 

Blacksmiths, Listen! Prepare for big wages 
in Navy and Arsenal with Toy's Modern Meth- 
ods doing hard jobs easy. Forging and making 
solid welds, hardening and tempering to a 
standard, with colored tempering charts. All 
for one dollar. Sample free. W. M. Toy, Sid- 
ney, Ohio. 

Authors! Your manuscripts criticized by edi- 
torial expert ; rewritten, revised, typed, sold. 
Heatley. 119-16 St., West New York. N. J. 

Flags and Decorations— American, Service and 
Allies' Flags in Silk, Bunting and Cotton, for in- 
side and outside decorating. Quick service via 
insured parcel post. Price list mailed the min- 
ute your request arrives. A. Fink & Sons, 
Wholesale and Retail, 56 North Seventh St., 
Philadelphia, Fa. 

Cats crave catnip. Send loc for a "catnip 
mouse" (a lifelike cloth mouse, stuffed with cat- 
nip). More fun than a "barrel of monkeys," and 
your "kitty" will like it. Address: Percy Ewing, 
Decatur, III. 

Cigarette, pipe or chewing habit conquered. 
Nature's method. Guaranteed. Write for free 
brochure. Edw. J. Woods, TA-300, Station F, 
New York. 

Tobacco or Snuff Habit Cured or no pay; $1.00 
if cured. Remedy sent on trial. Superba Co., 
SA, Baltimore, Md. 

Pyorrhea— H. E. Kelty, D. D. S., M. D., pyor- 
rhea specialist for 15 years, has developed a suc- 
cessful home treatment for pyorrhea. Purifying, 
healing, preventative. Full month's treatment 
and booklet $1.00. Circular free. Dr. H. E. 
Kelty, 106 Gladwin Ave., Leonia, N. J. 

Catch Fish. Descriptive folder containing valu- 
able information mailed for stamp. George 
Julian, Albany Building, Boston. 

"Opportunity Adlets" bring quick results. Our 
100.000 circulation, net. Other firms are making 
money — so can you. For proof address Classified 
Department, Electrical Experimenter, 22^ Fulton 
St., New York City. 

Wanted — Small Gasoline and Steam Engines. 
Cash paid for i to 4 cylinder light weight Motors. 
J-i to 10 H.P. Johnston, W'est End, Pittsburgh, 

Pa. 

Boys, Make Your Mother's Bluing, i pkg. 12c 
3 for 30C, 5 for 45c Each package contains 
enough material to make i gallon of full strength 
liquid bluing; will not streak; makes the clothes 
snow white. Kralovec & Co.. 2344 Alt geld St., 
Chicago, III. 
MiiMinaiim niHiimiiiiiiiiiMiiii wm BiiwnniiiiinHBB ii i i inii imrfniiiniiiTiiiiTi!nniimiiiai« 



Motion Pii ures 



Motion Picture Films 

list IOC, (J. Harrison, 
wood. Ohio. 



Any kind, sample and 
2^^ Lakeland Ave., Lake- 



Nezvs Correspondents 



Earn $25 Weekly, spare time, writing for 
newspapers, magazines. Experience unnecessary; 
details free. Press Syndicate, 566 St. Louis, Mo. 
iimimiufliinmnr niiii minni iiniiiTinTnmmiimiMifflimiiniiMmiiminauDigmninimitminnii^^ 

priutuig 

100 Bond Noteheads, 4 lines and 100 envelopes, 
prepaid, $1.00. Southwestern, 1413-H Berendo, 
Los Angeles. 

100 Envelopes and 100 Noteheads $1.00 prepaid. 
Any copy. Samples stamp. Elmira Specialty & 
Printing Co., 201 Madison Ave., Elmira, N. Y. 

Stamps and Coins 

Stamps— 65 different 5c to approval applicants. 
Michaels. 5600 Prairie. Chicago. 

202 different stamps 21c; 100 different U. S. 21c 
C. Reitter, Box 1054, Detroit, Mich. 

Full membership ISc, Collectors' Exchange 
Club. 45 Westminster, Worcester. Mass. 

We buy and Sell Old Money. $2 to $500 each 
paid for hundreds of coins dated before 1895. 
Keep all Old Money. Send 10 cents for new 
illustrated Coin Value Book, 4x7. You rnay have 
valuable Coins, get posted. Clarke Coin Com- 
pany, Box no, Le Roy, N. \. 

California Gold, Quarter size. 27c; Half-dollar 
size, 53c; Dollar size, $1.10; Large cent, 182a, and 
catalogue, roc. Norman Shullz, Kings City. Mo. 

Stamps— 61 all different free. Postage. ;jc. 
Mention paper . Quaker Stamp Co.. Toledo. Ohio. 

500 Finely Mixed United States or Foreign 
Stnnips. iJ. . rinl.itelic Star. Ma<lisnn. X. Y. 
ODBiiiimiminaunmMiUD lunuuiioiiiDiiioiiiuiiiiniiDjiipioii iu(] imn[uiiiiiii^ 

Xovelties 

Mechanical Novelty, barrel of fun. laughs and 
amust-ment, two 25c. Rullet Company, New 
Haven. Conn. _^ 

Nut Bowls and 60 other useful articles, made 
out of Native Myrtle Wood, the most beautiful 
finished wood on Earth. Send 3-cent stamp for 
illustrated descriptive catalogue giving delivered 
prices. J. H. Oerding & Sons. Coquille. Oregon. 

Send two dimes and get General Pershing on 
his horse in original colors, made of solid metal. 
Gem Novelty Co., 462 Wabash St., St. Paul, Minn. 



■BanifllllflimmmilinillDltmiNDiiaiiiaiiiBiMriwiimiiiiiiniiiiimianmiiriinniMmiiiwiimrtriirnni 

Business Opportunities 

linter a New Business. Earn $3,000 to $6,000 
yearly in professional fees making and fitting a 
loot specialty, openings everywhere with all the 
trade you can attend to; easily learned by any- 
one at home in a few weeks, at small expense; 
no further capital required; no goods to buy; 
job hunting, soliciting or agency. Address 
Stephenson Laboratory, 18 Back Bay, Bosto n, 
Make Die-Castings. Sketch, Sample, Booklet, 
and Proposition, 12c. R. Byrd, Box 227, Erie, Pa. 
Incorporate your business under the common 
law. No organization tax; no franchise tax; no 
federal corporation tax; certificates not taxable; 
stockholders exempt from company debts; do 
business anywhere; directors reside where you 
wish; lowest cost organization possible. Com- 
mon Law Organization Co., 4 Randolph, Detroit, 
Mich. 

Build up an Income in Oil— Others are doing 
it — Why not you. Today is the opportunity. 
Join our easy monthly payment plan NOW— it 
may mean hundreds in profits. Write for in- 
formation. National Oil Drilling Co., Dept. K, 
Houston, Texas. 

$30 a Week Evenings. I made it with a small 
mail order business — continued my regular job 
daytimes. Free booklet tells how, 2c postage. 
Alex. W. Scott, Cohoes. N. Y. 

"Opportunity Ad-Lets" bring quick results. 
Over 100,000 circulation, net. Other firms are 
making money— so can you. For proof address 
Classified Department, Electrical Experimenter, 
2ii Fulton St., New York City. 

Victory— Mechanical Toy Soldier window at- 
traction. 30 inches high. Salutes, turns head, 
points with finger, etc., as set. Well made, 
nicely dressed officers, privates, Uncle Sam. etc. 
Electrically operated. Does some stunt every 
half minute or oftener as set, and will salute 
soldier and pay no attention to others if de- 
sired. Representative wanted in each city and 
town. Write for prices. The John M. Biggs Co., 
Box 324, Chattanooga, Tenn. 

Make Big Money opening safes and setting 
combinations. Wayne Strong, P. O. Box 1430, 
Los Angeles, Cal. 

Patent Time-Actuated Electric Switch. Clock 
movement. For show window lighting., etc 
Turns circuits both on and off. Entire rights 
$1,000.00. Cato, 23iJ'S So. Sixth, Springfield, Illi- 
nois. 

Dollars Yearly in Your Back Yard. No gin- 
seng, mushroom dope. New ideas. Investigate. 
Particulars free. Metz. 313 East 89, New York. 

"Quick-Action Advertising— How it is Build- 
ing Business for the Progressive Advertisers of 
America"; A little story of RESULTS, told by 
the advertisers themselves — not the publisher. 
You will be interested in reading this little 
booklet, which we have prepared for prospective 
advertisers, a copy of which will be gladly 
mailed to you upon request. It tells you how 
to talk business with 1,000,000 intelligent, inter- 
ested and responsive Americans every month — 
men who know what they want and who have 
the money to buy it. Write for particulars and 
rates today. Douglas Wakefield Coutlee. 225 

West ^Qth Street, New V^'-V- 

nniiiiiiiiiniiiijiiiiiKifin ■^MM^^mimMMiiiiiiaipBiiii^'imiMS 
Blue Prints. Plans, Castijigs 

Amateurs & Mechanics get Detailed Blue 
Prints <r<n ' j H.P. Gasoline Engine. Postpaid, 
30c; "4 H.P. Horizontal Steam Engine, 50c; 5^ 
H.P. Vertical Steam Engine Sz Boiler, 70c; or all 
three for $1.00. Circulars on Engines and Rough 
Iron Engine Castings for Stamp. Universal Gas 
Motor Co.. S3 W- Jackson Blvd., Chic ago. III. 

Experimenters — Build your own spark coils, 
Wimshurst machines, motors, volt ammeters. 
Blue prints with instructions. Parts supplied, 
your parts machined, all repairs made. Send for 
particulars. Hubert Brunotte, 126 E. 85th St., 
New York City. 

PJwuoaraphs 

Build Your Own Phonographs and manufacture 
them for profit. Drawing instructions, Parts, 
Price List, Blue Prints, etc., complete, sent free 
upon request. Write today. Associated Phono - 
graph Co.. Dept. E-i, Cincinnati, Ohio. 

Build Your Phonosraph. "Perfection" high- 
quality spring and electric Motors, Tone Arms, 
Reproducers. Wonderful results. Big saving. 
New catalog and building instructions mailed 
for ten cents. Indiana Phonograph Supply Co., 
Indi anapolis, Indiana. 

Real Estate 

Sell your property quickly for cash, no matter 
where located. Particulars free. Real Estate 
Salesman Co.. Deor. ;8. Lincoln. Nebr. 

iuiiiiiiiiQ:iiiiiiiii[miiiiiiiii!iiiiif>iijiiuniiiimii;iiiiii!iiiiiiiiifimfi!im)iMioiittK^ 
Formulas 

160 Formulas, resilverincr mirrors, renewing dry 
batteries, luminous paints, mechanics' soap 25c, 
lists 2c. "Bestovall." Box 543-E. Chicago. 

For'thr I loir [ 

I Was Bald. Ubtami:;'! liair gr.iuth liv an In- 
dian's ointrnent containing genuine bear oil and 
rare plant juices. Many others have good hair- 
growing results. Will send box. postpaid, with 
recipe, loc. John Hart Brittain. 150 E. 32nd St., 
B A - in n, Nf w York. 

Continued on Page 7S8 



Yon benefit by mentioning the "Electrical Ext^crimentcr" when turtting to advertisers. 



758 



DontSend 
a Penny 

Here's the biggest bargain in boys' shoes you'll find 
anywhere. To prove it we will send you & psir without 

a penny of advance payment. Juet send your name 
and address. We ship on approval so you can compare 
them with other hi-top shoes costinR as much as W or 
$7. Ycu know how hard boys are on shoes. These are 
made for just that kind of 
ear— lo stand 



up under the 
hardest 
knocks a 
boy can 
Srive them. 
and you'll 
find these 
will outwear 
three ordii 
ary pai 
Prove it I 
our risk, 
them only if 
isfied. If not sat 
isfactory, return 
at our expense 




Make 
your boy 
proud and 
happy and keep 
his feet dry and 
warm with a pair 
of these wonderful 
Hi-Top Shoes, See how 
trongly they are made. 
Solidly made of strong wear-resist- 
ing rctanned leather. Two buckles and straps fasten 
closely around leg. Lace Biucher style on comfortable 
wide last — full round toe. All seams strongly sewed. 
Extra heavy solid leather soles and heels, to stand the 
hard'-st wear. Tan only. Sizes 1 to6. 

SEND no money— just your name and address. See 
if you can find their equal for J6 or even t7. 
Pay £090 '*"■ shoes on arrival. If not aatisfac- 
oniv *^«9X— tory. return them and we will refund 
your money. Be sure to state size wanted. Order by 
N'V Xl'^r??. 9--rt<i your order today. No risk to you. 

LEONARD-MORTON & CO.. Dept. X553 Chicago 



^Here's IKc New 
pmc/lulo -Wheel 



Write for Your Copy Today 

/T'S A BOOK brimful at intormatton 
a boy ought to have. It tells yuu how 
to organize an Auto- Wheel Coaster Club 
— how to make money with your Auto- 
Wheel — how to have most fun when camping 
and what to do in case of accident. It s a val- 
uable book — and it's yours for the asking. 

Get a Free Felt Pennant 

We want to tell you all about the wonderful 
Auto Wheel Coaster and tne patented Auto- 
Wheel Convertihle Roajlster— and to send you 
one of our beautiful Felt Pennants FKKE, 
When yoo write for the Autu-Wheel book 
givo OS the names of three coastir wa^fon 
dealer*, mentioning which one handles the 
Auto-Wheel, and we'll send you a complete 
Auto Wheel Catalog and the Pennant. KRKE. 
WHITE US A LETTER TODAY. Address. 

Buffalo Sled Company, 

163 Schcnck St., N. Tonawai.oa, N. Y. 




to Volumes 
t. 2 3. 4. 5 



INDEX 
ELECTRICAL EXPERIMENTER 

Postpaid 15c 

Experimenter Publlshlna Co . 231 Fulton SL N. Y. City. 



ELECTRICAL EXPERIMENTER 

EXPERIMENTAL CHEMISTRY. 

(Continued from page 751) 

3. The burning of hydrogen. 

4. Burning of arsin. 

5. Breaking up of arsin by heat. The 
solution of arsenic in sodium hypochlorit 
gives. 

6. 2As + SNaOCl + 3HiO = 2H3ASO. 
-r SNaCl. 

In the same manner as above, test some 
solution imagined to contain arsenic. 

Experiment No. 149. 
Perform an experiment using SbClj so- 
lution in e.xactly the same way as the 
.\sCL was used, and compare the results. 
Pay particular attention to the diflEerence 
between Sb and As in position of deposit, 
in color, and in solubility in NaOCl. 

Reinsch's Test. 
Experiment No. 150. 

Pour into a dish 3 or 4 cc. of a solu- 
tion of arsenious chlorid [AsCls] or so- 
dium arsenit [NasAsOa] acidified with hy- 
drochloric acid. In this solution place a 
strip of bright copper foil [about 3 cm. x 4 
cm.] and boil the liquid for three or four 
minutes, — longer, if no discoloration of the 
copper appears. 

What is the color? No change in the 
copper indicates absence of arsenic. In 
that case add more HCl and boil again. If 
ihe copper is finally discolored, take it from 
the liquid with the forceps, rinse it care- 
fully, and press it lightly between the folds 
of filter paper to remove moisture. Then 
cut it into small strips with scissors ; drop 
these strips to the bottom of a long and 
narrow test tube, and slowly heat the lower 
part of the tube. 

See whether the copper changes color. 
Look for a sublimat. State its color; its 
position. Is it in color and appearance 
like the sublimat in Marsh's test? Com- 
pare it with metallic arsenic, arsenious 
oxid, etc. Examine the sublimat under a 
microscope, breaking the tube and scrap- 
ing off a little for this purpose. Is it 
crystallin or amorphous? 

Experiment No. 151. 
Make arsenious sulfid [.-XsiSa], wash it 
free from impurities, dry it and put it away 
for future use. 

Experiment No. 152. 
Ascertain by experiment a solvent for 
arsenious sulfid [AssSs]. Try [NH.]j CO3. 

Experiment No. 153. 
Make Paris Green [Cu3[As03]:], wash, 
filter and dry, and put away for use. 

Experiment No. 154. 

Make arsenious oxid [As^Oj], using not 
over '/i gram. 

Experiment No. 155. 

See whether As^Oa is at all soluble in 
uater. 

Examine the various compounds of ar- 
senic with special regard to colors — red, 
yellow, green, and white — and attach 
names. 

(To be continued) 



JAPAN HAS WIRE-WIRELESS 
CENTRAL. 

An exchange to wireless and wire tele- 
phones is to be establisht in Kobe very 
shortly by the Government Department 
on Communications. A wireless tower 180 
feet high is now being erected in front of 
the largest of the Kobe telephone exchanges. 
Wireless telephone messages from vessels 
within 100 miles of the South Japan port 
will be connected by "Are you there?" 
ffirls with the telephones of subscribers in 
Kobe, Osaka. Kyoto and neighboring cities, 
thus serving the most densely populated 
section in Japan. 



February, 1919 

Opportunity Ad-lets 

Continued from Page 757 

Tricks, Puzzles and Games 

1000 stage tricks with 500 illustrations. Cata- 
logue IOC, small catalogue FREE. Hornmann 
Magic Co., Sta. 6, 170 Eighth Avenue, New York. 
Black Art Hindoo Experiments, copyright 1919 
Edition, 25c. Invisible Ink. Free Trick. Cata- 
logue each order. Lindhorst Magic X Shop, St. 
Louis. 

Tricks, Puzzles, Jokes- Toys, Games, Novelties, 
Doll and Cane Racks, Plays, Wigs, Stage Sup- 
plies, Escapes and Illusions. Large 1917 catalog 
free. Oakes Magical Co., Dept. 549, Oshkosh, 
Wis. 

Magic Card Trick, Get these magic cards and 
fool your friends, loc. Reeves & Taylor Magical 
Co., West Somerville, Mass. 

Magical Apparatus and Ventriloquist Figures. 
Lowest prices. Catalog, Magic and Ventriloquist 
Lesson free. Write, Sylvian s Magic Shop, E-1Q2 
Clifford, Providence, R. I. 

Wireless 

Better stock up now on switches and switch 
points for that new set. Circular describing the 
most perfect on the market sent free. Eureka 
Secondary Co.. 6939 S. May St., Chicago. 111. 

Rare Radium Ores. Radio- Activity Experi- 
ments. Photograph thru opaque matter, dis- 
charge electroscope, etc. One 5% uranium oxide, 
other 12%. Both complex chemically. Ten to 
twenty metals. Half ounce first, quarter second, 
gram uranium oxide, all for $1.00. Full descrip- 
tion with order. O. I. Lee, 2869 Boulevard, Jersey 
City, N. J. 

Build a Radio-Airo Station— Blue print, plans, 
photograph 18-22, prepaid, $5. Wm. J. Rogers, 

3S; Mnrisse..- Ave,. Haledon, N. J. 

. '.)|HL liiiiogiiiljiiiiiHiJBHHHMHl 

Electrical Supplies & Appliances 

Recharge 25 Dry Cells for five cents. Direc- 
tions 10c. Gilbert, 28 Chestnut, Binghamton, 
N. Y. 

Mechanics — Quickest method of making tapers 
in the lathe, 25c. Charles Fleischer, 1389 St. 
Marks Ave.. Brooklyn, N. Y. 

Electrical Tattooing Machines and Supplies- 
Catalogue free. Prof. Temke, Exp., 517 Central, 
Cincinnati, Ohio. 

Supersensitive Microphones for Wireless Con- 
trol of Lamps, Alarms, Motors, Guns, Toys, etc., 
by sound waves of a whistle. Description and 
drawings free with each instrument. Price $2.10, 
postpaid. Tames A. Campo, Suite 1316, 32 Nassau 
St.. New York, N. Y. 

Amateurs ! — Make simple electric motor that 
works. Instructions 25c. Box 5, Hingham Cen- 
trf. Mass- 

Mr. Business-Man— Your advertisement here 
will be read by over 100,000 live prospects. The 
"Opportunity Ad-lets" of the Electrical Ex- 
perimenter bring quick and positive results. 
For proof of what they have done for others ad- 
dress Classified Department, 233 Fulton Street, 
Xcw York. 

Plioto DevclopiK.! 

Mail Us 15c with any size Film tor development 
and 6 velvet prints. Or send 6 negatives any 
size and 15c for 6 prints, 8 x 10" mounted enlarge- 
ments 35c. Prompt, perfect service. Roanoke 
I'lioto Finishing Co., 255 Bell Ave., Roanoke. Va. 

Clean, Neat, Perfect Kodak Finishing at the 
lowest prices. Work returned the same day re- 
ceived. Send film for sample print and copy of 
Catalog on Developing, Printing, Enlarging and 
Hand Coloring, also copy of Photo Craft Maga- 
zine which will help you make better pictures. 
Photo Craft Co., Box 69, Ann Arbor, Mich. 

Postcards 

tverything in Postcards. Live-wire list free. 
Worth-while samples 25c. Mention subjects pre- 
fcrre'i. Mutual Supply Co.. Bradford, Pa. 

Five Prettiest Women Cards, hand colored, 2SC. 
Durso. Dept. 41, 25 Mulberry, N. Y. City. 

^[pl■l^lll^lllal tm^g^ll^^llr■llfnr ln^tl^lHllllIn1^fa^mll^lllllnmTll■lfl■ltl■llI■lll■U» ^ ' ■l■lll■l^ 

For Advertisers 

Unheard-of Trial Offerl " 

rd classified advertisem 
Record Advertiser, Box 2E. Houston. Va. 



Inch display or 30- 
word classified advertisement ten weelcs, $1.00. 



"Quick-Action Advertising— How it is Building 

Busmcss for the Progressive Advertisers of 
America"; A little story of RESULTS toM by 
the advertisers themselves— not the publisher. 
You will be interested in reading this little 
booklet which we have prepared for prospective 
advertisers, a copy of which will be gladly 
mailed to you upon request. It tells you how 
to talk business with 1,000,000 inteiligent. inter- 
ested and responsive Americans every month — 
men who know what they want and who have 
the money to buy it. Write for particulars and 
rates today. Douglas Wakefield Coutlee, 225 



West 3Qth St.. New York. 



'Opportunity Ad-Lets" bring quick results. 
Over 100,000 circulation, net. Other firms are 
making money — so can vou. For proof address 
Classified Department. Electrical Experimenter, 
2;,T Fulton St.. New York City. 



K«« b^ntUt by m€fU%9nimg th4 "BUctricaJ Experimenter'' when writing to advertisers. 



February, 19 19 



ELECTRICAL EXPERIMENTER 



759 



\ 




This masterpiece contains 1 60 pages, 400 illustrations. 
Size of book 5"x9". Printed on extra thin paper, so book 
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cover. FREE with a year's subscription. 

Add 5c for postage. 



The most comprehensive Wireless Course ever printed. 
Contains 160 pages, 350 illustrations. Size of book 
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FREE with a year's subscription. 
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» 



This is a very limited offer. It may be withdrawn at any time, due to the 
tremendous cost of paper, which IS JUST DOUBLE WHAT IT WAS ONE 
YEAR AGO. We have only a limited supply of these fine books on 
hand; after they are gone we cannot reprint the books until conditions 
become normal again. THIS MAY BE TWO YEARS OR MORE. Now is 
your chance. 

The publishers of this journal have earned an enviable reputation of giving 
more than 100 cents' worth for each dollar spent with them. Profit 
by this liberal opportunity NOW; it may never be made again. 

HERE'S THE OFFER 

Subscribe to THE ELECTRICAL EXPERIMENTER for one year, 
at the regular subscription price of $2.00 per year (Canada, 
» \^^^k foreign and N. Y. C. $2.50) and we vrill send you FT^E, 
Gentlemen: N^ i^^_ POSTPAID, either one of the above books. If you sub- 
scribe for two years, BOTH BOOKS WILL BE GIVEN 
FREE, POSTPAID. 

If you are a subscriber at present, take advantage 
of this wonderful opportunity anyway. If you 
do, we will extend your present subscrip- 
tion for one year. 

.^__ This Offer Limited. 

'"™° ^""^^^^ 223 FULTON STREET 

**!«« '^N'Y^^ ^^^ YORK CITY 



2-18 



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You btneSt by mtnHoning th* "EUctrical Experimenter" when writine to advertisers. 



760 



ELECTRICAL EXPERIMENTER 



February, 1919 



GREATEST TOY SENSATION OF THE DAY! Boys, you can have Movies at vour own home with this latest modal 

F!5«miR«^ADHAUGHT MOVING PICTURE MACHINE 

^1^ I Ti .•>i«nd.rd Filmi »«me »a the lareer mcchino- Very ckBily mnnadcd. 

^-M *£^rV^^ Si(npl> rurn ihe hnndlr Good Variety of Film* ktwnyt obtainable 

rniUC ONLY 5>^»OU Including Two Filma 



Here is a nv-""-"^^' ^^ 
Uncle SamsJSghtir.e 
moDtters. Eisbt 
t) i S eon s. each 
of which tluhes. St 
correct intervals, 
from twelve to 
twenty times. Extra 
unreunition aiwa\-» 
obtainable. Abso- 
lutely harmless. Can be oi>era«>.:l 

two' H 




"The Baby" rrr Revolver 

A HA NDSOME AND MOST EFFECTIVE WEAPON 

«P(^Ow ^s**"^ .y"*******s^ Me««ur«» but 

■~ * ^ ^ * nehes Ions 



•Mr fhai 
th*N^-l ■'t It i« 'oQ cm i.'" .■>• iTf • 
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THIS IS A GENl'INE MOVING PIfTL'HE MArHINf 
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The Moving Picture Morhlne Is finely construcietl. niv 
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aied l.y ii finely constructed mcrhanlsm. The prujii-i- 
Ing lenses are carefully ground and adjusted, tilph 
polished, standard double exira rellecior, thr.iwinB .' 
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three or four feet In area. The 
I by a safety carbide generator. 

RAuf *A»iMaa« AI*M««. ""''" •** '^ "-'*''^ "" ^^^ largf.st automobiles, This 

mySreriOUSUnOSt throws a dazzling whUe light on the screen. 

rt*.'?,T,'?.T."'n'"»7'; ^' '" a EoUdly constructed and durable Moving 

[*.c.i. -No !.»» pr«u..i Picture Machine. The mechanism Is exceedingly 

c;I^..»S^'iB*'I*Ji"rfMU? *'"'P'* aid l" readily operated by the most Inex- 

ar\ pi«r»^ ric*. wioi • perlencrd. The pictures shown by thl9 m^rvelotia 

* "4'- Moving Picture Machine are not the common 

iwuor crude and lifeless Magic Lantern varletv, but ar" 

-«- "il life-like photographic repro-Iactlon<i of actunl 

TMhS «■■*"*'. places, and people which nr-ver tire Us 

,.p,f,- audiences This Mo\lng Picture Machine has 

^"t*' .aused a rousing enthusiasm wherever it was used. 

t"*^' JOHNSON SMITH A, CO. 

Dflpt. E 3, 64 West Lake Street. CHICAGO 




watch. 




;.^ ■ ■ ■ .'■ „:i»i nutcS 

jOHNaoN aMiTN a coT 

WATCH CAMERA 

Ths moat wonderful snd In- 
flanloua Camara mada 

ittlt> lamer tbaa • 
bicb It cloaety ro- 
embifw. Vou cun carry 
the CMpo about Id your 
packet and take pic 
turi'B nitliout any one 
belDS the wl»er. 

Ont Cant a Pleturt 

T)i<9 Eipo loBd* In d»xliKht 

wllh 2li Eapoiurs Pilm>, c*«t- 

1n« ibc. Ihui Ui* picture tak- 

ina part of • *hals day'* mtt- 

Intt oiar ba had lot Ui« nominal 

aum of SAc-On* crni ■ pirlun. 

lu Eipoaurg Film* alao obtain- 

■^ IIU •tDiplieltr llirir lo OIK 



natantanaou* ahutlar* : 
ouncaa : nlckrl plalad. 
Thsroufhlj crKctteak— 
camcru-ln dally uaabr 

ncral public. Impurtanl 

•q'ual to anr caman on Uia 

Exp* Watch'c>m«rB » A cA nUll, 10 (j „. 

Ntlin lOc ftRnrora «C(OU tuihii roa*1 C*rrilit tu*. }Sc 

JOHNSON SMITH * CO.. Dppl. E S. S4 W. Lah* St.. CHICAGO 

Trim Your Own Hair With the 

Utility Safety Hair Gutter 

■^;n Cull tha Hair Any Langtii, 








lo ahava the faca or HnUt 










•nd u>e lh« 














«."..TJJ 


Flnltb uroimd 


or "eat Btfpa- 


injoDrhalt 



Kunxtl guide* the cutt«r biiia ovaolr 

1o«p puah the blado ontJl tb« coltlnc adsa la avca 

ck It can bo uied a* an ordinary ruur ty 
.0 hHdir. tho .■uitm« «l«e balnit lo lh» 

, . , _, ^ ', P'"" the blaJo"n (he' hulder. wilhVhV^cutllnB SiS'tn 

Li-. I hark. novlDK Ihu blado out until tba eulUnir ids* la clrurot I he bark of Iho 

I0HN50N SMITH A CO.. Dapt. E 3. ^4 W. Lak* Si!,' CHICAOO 






% ROPE SPLICING 



NEW 
OOOK 
USEFUL KNOTS, HITCHES, SPLICES. ETC. 

H«» Difltnnt Knoli Are Made ar.d What The* Ai 
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A mow pracikil t,Bi>ilt-<ok e'-''U.a coiuylcte or..! 
lloiplr dlrn-iK.n for tuaklt^s all U.t tot»l uai-ful 
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r^^rr, Prle» ?0c p. od. 
JohnaoD Mnlih & * o.. Dept. E 3. M W. Ijikr fit . < hlcagi 



LUMINOUS PAINT 



Make Your Watches, Clocks, Etc., 

Visible by Night ^ ' ^^.''^^"'H^,^,T^ '%«' 



Each Ixu contains 12 Eggs, 
which arc no lart-cr than 
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When lit with a 
match, however, 
each one gradu- 
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feet lonir, which curls and twists atmut 
in a most lifelike manner, frlet pari 
bai lOe, pettpald. Johnson Smith A Co. > 

CIGARETTE ROLLER 



New 

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ready mode. 

[iTinKiibout half of 
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A Grtat Curioiity 

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latioai lie t'amoaa Uaamarluri P.^n'na ihiTi' V-ri l'.^""."* ■"■He tu rhanve info a coin of anuUier 

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H£rt(H*J InaUvfllpna, tor ttbkh »or, ran ea.ll. «,.k. ,.» „,~..,re tho necaaaarr apparalua 

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paiCe COMPLETE 6««LT so CENTS. 

0»0t. E 3. 



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l»r»f<l«-m»in a/id iraloahle Mnta Ui amatimr 

JOHNSON SMITH « CC 






. THtMENDIS THK STM'iNGEST SHdT IN TH 



S4 W. Lake St., CHICAGO 

The Newest Novelty Aerial Balloon 

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Mactt U-TTOT uka 
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sV UMBRELLA PALM 



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.. y.,,. will be ablo to .jl.penae w"h th.- aid of Ih.. \amp- 

«u.».pd.j«haMnSniltliftCo..0«itlK3.S4W.lJli«St.,ChJuta 
THE GREAT 1 
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Grrat Jupunciu Unihiolln I'nlm In o eeTnlaqoado 
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y pain). like appeai-nce, sa 

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3369 3;! 



Just what you need to know to succ eed in ELECTRICITY 

EVERY electrician, every engineer, every mechanic should know 
about these wonderfully helpful instructive books, which give in 
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You run into some new electrical problem almost every day. The 
information you need to help you in your every day work is in 



H AW KINS 

ELECTRICAL GUIDES 

These books place electricity at your finger ends. They cover every imaginable 
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yeari— but 1 wish I had these books 

years ago, as they have saved me a 

gr«at deal of trouble." H. Marshall 

Steamer M & B No. 2. 

WalkervUle, Ont. 



The books are small enough to slip into your coat 
pocket — handsomely bound in flexible black covers. 

You can carry each volume mth you until you have 
mastered its contents, 3.500 pages of actual information 
and 4.700 illustrations. Once you see these books and 
put them into actual use you will never again want to be 
without them. Try it at our expense. 



SEND NO MONEY 

It win cost you nothing to receive tliese books — to look 
them over — ask them all the questions you can think of 
— use them in your work — study them — pick up some in- 
formation that will increase your earning ability. We 
will ship you the entire set of 10 volumes entirely FREE. 

This is a sign of our confidence in the guides. Pure 
gold does not object to being tested. Keep them for 
seven days and if you do not decide that you can't get 
along without them, return them to us and owe us 
rothlng. 

When you decide to keep them you only have to pay 
$1,00 down and remit the balance of $9.00 on the easy 
payment of $1.00 a month till paid for. 

Use this coupon to get the books. Xt will pay you 
many times over. 

THEO. AUDEL & CO. 
72 Fifth Ave. New York, N. Y. 



5END NO MONEY- U5E THE COUPON 



READ THIS PARTIAL LIST OF CONTENTS 

No 1 Contains 348 pages, 388 Illustrations. Electrical 



signs and symbols — ^static and current electricity 
—primary cells — conductors and Insulators^ resistance and 
conductivity — magnetism — induction coils — dynamo principles 
— classes of «i>'uamos — armatures — windings — commutation — 
brushes, etc. 

M-» O Contains 348 pages, 394 illustrations. Motor 
IIU* A principles — armature reaction — motor starting — 
calculations— brake horsepower — selection and installation of 
dynamo and motors— galvanometers — standard cells — current 
measurement — resistance measmement — voltmeters — watt- 
meters — watt hour meters — operation of dynamos — operatioa 
of motors, etc. 

Mq 3 ^^ontains 300 pages, 423 illustrations. Distribution 
** systems — wires and wire calculations — inside, out- 
side and underground wiring — sign flashers — lightning pro- 
tection— rectifiers— storage battery systems, etc. 
No 4 ff'^'ains 270 pages, 379 illustrations. AltemaUng 
current principles — altemathig current dJtgrami 
— the pnwer factor — alternator principles — alternator con- 
strue tion^win dings, etc. 

No *> Contains 320 pages, 614 lllu3tr(.tion9. A. C. Motors 
i^u* %» --sjmchronousandinduction motor principles — A. C. 
commutator motors — induction motors, transformers; lossei. 
construction, connections, testa — converters — rectifiers, etc. 
No ^ Contains 298 pages. 472 illustrations. Altemttlng 
• ^ current systems — switching devices — circuit break- 
ers — relays — lightning protector apparatus— regulating devices 
— synchronous condensers— indicating devices— meters — power 
factor indicators — wave form measurement — switch boards, eto. 
M|^ n Contains 316 pages, 379 illustrations. Alternating 
*''^* • current, wiring power stations— turbines; manage- 
ment, selection, location, erection, testing, miming, car* and 
repair — telephones, etc. 

No R Contains 332 pages. 436 niustratJons. Telegraph 
iiv» \j —simultaneous telegraphy and telephony — ^ 
wireless — electric bplls— electric lichflne— photometry, ftc, . ^ 

No Q Contains 322 pages. 627 illustrations. El*>c- ^ 
* "• *' trie railways— electric locomotives— rar llghi- ^ 
ing — trolley car operation — miscellaneous appllcatlona — ^ 
motion pictures — gas engine ignition— automobile self- ^F 
starters and lighting systems, electric vehicles, etc. ▼ 
No in '^'•"t^ins 513 pages. 599 illustrations. ^ 
^'"* *" Elevators — cranes— pumps— air com- ^r 
pressors — electric heating — electric welding— ^ TH^O 

soldering and brazing— industrial electro- ^ Aiinci Pc^* 
Ivsis — electro plating — electro-therapeutic ▼ AUUtL ot UU. 

—X-rays, etc. ^ 72 Fifth Avenue 

Also a complete 126-page ready ^r New York, N. Y. 

reference index of the complete ^ 

library. This index has been ^r Pleas© submit me for 
planned to render easilv ac- ^ examination Hawkins 

••essible aH the vast infor- M ^P^^l^^"^^ ^2^^^ (price 
▼^ Jl each). Ship at once, pre- 
\ paid, the 10 numbers. If sat- 

isfactory I agree to send you fl 
within seven days and to further 
mall you $1 each month until paid 



mation contained in the 

10 electrit-al guides. 

There are over 13,- 

500 cross refer- a 

ences. You find ^^ 

what you want ^^ E'.gnature 

to know in- ^^ 

stantly. ^ n.„...,finn 



J 



Business Address 



let , E.E. Feb. 



y« beneht by menttoning the "Electrical Experimenter" when writing to advertisers. 




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f 




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i TREATS SUCCESSFULLY 




I -Abscesses 


..Facial Neuralgia 


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■■aiaii »iA>iri 1